President Donald Trump told Vice President Mike Pence and other administration officials to tone down the rhetoric in the weeks before his historic summit with North Korean President Kim Jong-Un, it was revealed on Sunday.

Trump had led the tough talk against Kim earlier in his administration, calling him a 'rocket man' in his September speech to the United Nations.

But as then-CIA director Mike Pompeo prepared to go to North Korea over Easter weekend, the president changed his tune, according to The Wall Street Journal.

The president surprised top advisers by urging restraint, officials told the newspaper.

National Security Adviser John Bolton and Vice President Mike Pence were told to tone down their comments.

'Mike, you got it?' Trump told the vice president, a person in the room told the Journal. 'No f***ing crazy talk from anybody in the administration.'

Trump also told Pompeo the administration wasn't going to change its policy but also needed to give North Korea room to negotiate.

One White House aide said the president, in general, has 'unrealistic expectations.'

President Donald Trump is met by Singapore's Foreign Minister Vivian Balakrishnan and other officials after arriving for his summit with North Korea

The president's foreign policy prowess is under scrutiny ahead of his meeting with North Korean President Kim Jong-Un

Trump ordered Vice President Mike Pence and other aides to tone down the tough talk on Kim ahead of the summit

'He has unrealistic expectations,' said one top administration adviser, 'and I mean that as a compliment.'

Another tactic the president likes to use in his negotiations is the art of the deadline.

'He never gives an order without a deadline,' an administration official told the newspaper.

He uses deadlines as a weapon - either out of rush to want to make a final decision or to create deadlines with consequences to prevent others from running out the clock.

Trump also likes to make negotiations personal and is comfortable breaching carefully choreographed diplomatic protocol to do the talking himself.

When Chinese President Xi Jinping visited Mar-a-Lago in April 2017, Trump upended weeks of international negotiations by asking for an immediate one-on-one meeting with Xi.

'Got a minute?' he reportedly asked Xi and took him for a walk across the grounds much to the frustration of the Chinese delegation, who were unhappy with the breach in protocol.

'They were legitimately losing their minds,' said one aide present.

His personal touch also causes anxiety for the White House staff, some of whom said they worry his praise can leave foreign leaders thinking U.S. policy has changed.

Trump's foreign policy making prowess is being closed watched as he arrived inSingapore Sunday for talks that could change the course of history and earn him the Nobel Peace Prize, if successful in convincing the world's most isolated nation to end its pursuit of mankind's most deadly weapons.

After a grueling 21 hours of travel that included a refueling stop on a Greek island, Trump touched down at Paya Labar Air Base on Sunday evening. He gave a short wave as he deplaned, and told journalists nearby he was feeling 'very good' about his meeting on Tuesday morning local time with Kim.

Following a short conversation with Singapore government officials sent to greet him, the U.S. president then sped off in his motorcade to conclude his first evening in Singapore in the privacy of his room at the Shangri-La, the luxury hotel housing the U.S. delegation.

Monday, he meets with Singapore Prime Minister Lee Hsien Loong, following in the footsteps of Kim, who sat down with the head of the summit's host nation after his own arrival on Sunday afternoon local time on an Air China flight.

Kim is staying at the St. Regis hotel, just down the road from Trump. The foreign leaders will hold their summit at a third location, the Capella Resort, ensconced on 35 acres of land south of the city on Sentosa Island.

'We're going to have a great success,' President Trump boldly predicted on Thursday at a White House news conference. 'A long time ago, this could have been solved in a lot easier manner and a lot less dangerous manner. But it wasn't. So I'll solve it, and we'll get it done.'

After pitching himself as the world's greatest negotiator with an unmatched ability to drive a bargain, Donald Trump will have his shot this week at one of the white whales of high-stakes deals: a North Korean nuclear accord. Trump is seen here arriving Sunday night in Singapore

After a grueling 21 hours of travel that included a refueling stop on a Greek island, Trump touched down at Paya Labar Air Base on Sunday evening

He gave a short wave to the press, and told journalists nearby he was feeling 'very good' about his meeting on Tuesday morning local time with Kim Jong-un

US President Donald Trump (C) is welcomed by Singapore's Foreign Minister Vivian Balakrishnan (L) after Air Force One arrived at Paya Lebar Air Base in Singapore on Sunday evening

In this photo released by the Ministry of Communications and Information of Singapore, Singapore Minister for Foreign Affairs Dr. Vivian Balakrishnan greets Kim at the Changi International Airport on Sunday

Police officers patrol outside the Shangri-La Hotel in Singapore ahead of the summit between Trump and North Korean leader Kim Jong Un. Trump is staying in the Shangri-La for the duration of the summit

A vehicle believed to be carrying Kim Jong Un travels through Singapore on Sunday

Spectators gathered to watch the Air China flight carrying Kim land on Sunday afternoon local time in Singapore

A first-term president with no prior political experience who has a flare for the dramatics, Trump's skeptics say this week's summit with Kim will serve as little more than a misguided photo-op.

His admission in the lead up to the trip that he'd done little to get ready for the face-to-face with the 33-year-old dictator and was relying on his 'attitude' and 'willingness' to strike an accord did little to lessen anxiety at home that Trump would make a catastrophic mistake.

Senate Democratic leader Chuck Schumer on Thursday chided that 'the situation is far too dangerous for seat of the pants negotiating' after warning Trump earlier in the week against entering an agreement with Kim 'just for the sake of reaching a deal.'

The sniping from the sidelines prompted Trump to charge that Schumer and his party 'did NOTHING about North Korea' and is now 'telling me what to do at the Summit the Dems could never set up.'

'Schumer failed with North Korea and Iran,' he tweeted, 'we don't need his advice!'

The 71-year-old billionaire whose birthday is Thursday reassured naysayers Friday that he has 'been preparing all my life' for the showdown with Kim and said Saturday at a media availability that 'within the first minute' he expects to know if his negotiation partner is serious about denuclearization.

'I think I'll know pretty quickly whether or not, in my opinion, something positive will happen,' Trump said at an impromptu news conference after the G7 summit. 'And if I think it won't happen, I'm not going to waste my time. I don't want to waste his time.'

Trump has repeatedly said he will get up and leave the meeting that he now claims will be only a first step in the direction of North Korean denuclearization if talks are not productive.

'I think it's a 'getting to know you' meeting, plus,' he said last week, setting expectations, after a visit from Kim's lead negotiator. 'And that can be a very positive thing,' he added.

A first-term president with no prior political experience who has a flare for the dramatics, Trump's skeptics say this week's summit with Kim will serve as little more than a misguided photo-op

Following a short conversation with Singapore government officials sent to greet him, the U.S. president then sped off in his motorcade to conclude his first evening in Singapore in the privacy of his room at the luxury hotel housing the U.S. delegation.

Kim and Trump are not in the same hotel. the North Korean dicator is staying at the nearby St. Regis hotel in Singapore during the summit

Police inspect vehicles at a checkpoint at the back of the St Regis Hotel on Sunday

Members of the North Korean delegation are seen in Singapore on Sunday

Security was heightened outside of the hotels the two men are staying at, as well as the site of the summit on Sunday

Trump's determination that he would not be able to persuade Kim in one sitting to drop his country's decades-old pursuit of a nuclear warhead with the power to destroy cities inside the United States provided for an easy-to-meet goal for his administration – just showing up to the meeting he called off once already.

'I did it once before,' he pointed out Friday at a Rose Garden news conference. 'You have to be able to walk away.'

For Kim to get a sustained audience with the president or a visit later in the negotiations to the White House, the Trump administration says North Korea will have to do more than exchange niceities.

A detailed task list and timetable for disarmament, however, has not been communicated by the U.S. government.

'I think it's a process. I've told you that many times before. I think it's not a one meeting deal,' Trump told reporters Thursday. 'It will be wonderful if it were.'

The U.S. president and former reality TV star insisted that the meeting will be 'at a minimum' the beginning of 'a good relationship' between himself and Kim.

'And that's something that's very important toward the ultimate making of a deal. I'd love to say it could happen in one deal, and maybe it can,' he said. 'They have to denuke. If they don't denuclearize, that will not be acceptable. We cannot take sanctions off; the sanctions are extraordinarily powerful.'

Trump's administration has been unwavering in its demand that North Korea must completely and verifiably end its nuclear weapons program to earn sanctions relief.

The Trump administration and North Korea have wildly different interpretations, though, of what it means to denuclearize the Korean Peninsula.

For North Korea, the Heritage Foundation's Bruce Klingner explains, denuclearization includes 'anything that impacts or influences' the land mass, including nuclear-capable submarines and aircraft in Guam.

'So if the president is going in and not realizing how North Korea defines things, and that if you don't have clearly delineated text,' he said, 'then you might agree to something verbally or on paper, where North Korea has a far different interpretation of it than the US. has.'

Singaporean gather in front of the Istana Presidential Palace, where North Korean Leader Kim Jong-un and Singapore Prime Minister Lee Hsien Loong were about to meet in Singapore

Kim meets with Singapore's Prime Minister Lee Hsien Loong at the Istana on Sunday

The two letters met for private talks prior to Trump's arrival; the U.S. president will take his turn with the PM on Monday

Kim Yong Chol, a close aide to North Korea's leader Kim Jong Un, walks in the Istana

Police officers escorting the motorcade of Kim park after he arrives at the Istana

Secretary of State Mike Pompeo has twice met with Kim since early April to lay the groundwork for this week's talks. He said Thursday that the U.S. had narrowed the gap between its vision of denuclearization and the one that's being used by North Korea during recent sessions, yet declined to say exactly where that leaves the two parties.

'What I have said publicly is he has indicated to me, personally, that he is prepared to denuclearize; that he understands that the current model doesn't work, that he's prepared to denuclearize,' Pompeo told journalists from the White House's podium.

Alluding to a failed deal with North Korea that former President Bill Clinton's administration brokered and one with Iran that Barack Obama's government signed and Trump last month withdrew from, Pompeo said Kim 'understands that we can't do it the way we've done it before' and that denuclearization cannot be a years-long process.

He allowed that 'this doesn't happen instantaneously' and will take time.

'But that the model for succeeding — security assurance; and political normalization; and denuclearization completely, verifiably, and irreversibly — for that to take place, we've got to make bold decisions,' he stated.

Trump has targeted North Korea with what his administration calls a 'maximum pressure' campaign meant to starve Kim of the resources and funding he needs to fully realize his country's long-held nuclear ambitions that he has pledged to keep in place into the brutal leader who ascended the throne in 2011 breaks.

The international sanctions levied by the United Nations, and layered on by the U.S., have mostly cut North Korea off from crude oil and outside transactions of any type.

'I could add a lot more, but I don't — I've chosen not to do that at this time,' Trump said Thursday in an admission that the U.S. is not using 'maximum pressure' to break North Korea. 'But that may happen,' he said during remarks in the Oval Office with visiting leader Shinzo Abe.

He said later, at a joint news conference with the Japanese prime minister, that use of the term 'maximum pressure' at all following his conversation with Kim should serve as a red flag to those reading the tea leaves about the outcome of the tete-a-tete.

'We don't use the term anymore because we're going into a friendly negotiation. Perhaps after that negotiation I will be using it again,' he stated. 'You'll know how well we do in the negotiation. If you hear me saying we're going to use 'maximum pressure,' you'll know the negotiation did not do well, frankly. There's no reason to say it.'

The jet carrying Kim landed at Singapore's Changi airport on Sunday afternoon amid huge security precautions on the city-state island

In this Saturday, June 9, 2018, photo, a surveillance camera is seen at the entrance to the driveway of Capella Hotel in Sentosa, Singapore. A new surveillance camera is installed and restaurants closed on Singapore's Sentosa Island, a popular tropical getaway now easing into the political spotlight ahead of Tuesday's summit

The historic summit between U.S. President Donald Trump and North Korean dictator Kim Jong-un will be held at the Capella Hotel on Singapore's Sentosa Island

It was restored as a five-star hotel in 2009 by British architect Norman Foster and still retains many of its colonial features

North Korea, for its part, was listening out for another term in the United States' rhetoric that it deemed too aggressive – the 'Libya model' for denuclearization. Kim's regime beat up both the president's national security adviser, John Bolton, and his vice president, Mike Pence, for using phrase that has historically negative connotations.

Libya's Muammar Gadhafi was ousted and executed following a voluntary abandonment of nuclear weapons that he thought would be accompanied by assistance and protection from the United States.

Gadhafi did not have a formal agreement with the U.S. like the one that Trump is pledging to strike with North Korea. Nor did he receive the type of assurances that he'd be propped up as Trump has done for Kim.

Trump says the U.S. will make sure that Kim remains in power if he denuclearizes. He has also floated economic prosperity, in the form of new investment from American companies, as a motivator for Kim to decide he's worthy of doing business with.

For Kim to take the enormous risk of ending the nuclear weapons program that made him a household name around the world to begin with, North Korea has said it will need hefty security assurances that it has not entirely outlined publicly.

Former CIA Director James Clapper says Trump should agree to a diplomatic presence in Pyongyang. The ex-spy chief says that Trump should recognize that Kim's regime is likely to ask for a commitment from the United States to pull back on its military presence on the peninsula.

'We should be mindful that that could easily be a two-way street in that the North Koreans could easily demand that we denuclearize, meaning no more B-1's, B-2's or B-52's on the Peninsula, or within operational proximity of the Peninsula,' Clapper said last week in an interview with radio host Hugh Hewitt. 'And I hope we're ready to deal with that. They are paranoid about our bombers.'

Where will the summit be held? The macabre history of Sentosa Island where Trump and Kim will meet Restaurants have been closed and a new surveillance camera was installed on Singapore's Sentosa Island - a popular tropical getaway that has been thrust into the spotlight ahead of a summit between Donald Trump and Kim Jong-un. The resort island plans to keep welcoming tourists this week despite boosted security for the summit at the 112-room Capella Singapore hotel. A group of journalists gathered outside the hotel and across the road, waiting for signs that officials had arrived. But only authorized vehicles were allowed to enter, and hotel restaurants were not taking reservations until after the summit. Police have marked the island and some of its surrounding waters as a 'special event area,' where loud-hailers, flags or banners over a metre-long or wide are banned. Part of the facade of the five-star Capella Hotel (pictured centre) is seen on Sentosa Island in Singapore, where Donald Trump and Kim Jong-un will meet Located a quarter mile off the coast of Singapore, Sentosa is no stranger to celebrities and VIPs. It is linked to the city by a bridge and home to high-end resorts, golf courses and a large amusement park. But the macabre history of the island, which will become the venue of the historic summit on Tuesday, is less known. In the 18th century, when Singapore was a British colony, an unknown epidemic killed off most of its population of 60. Only two households survived. During World War II, the British used artillery forts and a battery on the island to unsuccessfully fend off a Japanese invasion, which transformed it into a prisoner-of-war camp. It's no wonder the island was known as Pulau Blakang Mati, which roughly translates as 'island of death from behind.' In 1970, the island was renamed after a nationwide contest. Sentosa was subsequently developed as a resort and expanded on reclaimed land. Technicians install a surveillance camera at the entrance of the five-star Capella Hotel on Sentosa island on Saturday Nevertheless, Lee Kuan Yew, Singapore's prime minister from 1959 to 1990, used the island to hold long-term political prisoners who were often detained without trial. Chia Thye Poh, a former member of parliament, spent 23 years in jail and under loose house arrest there. He worked as a freelance translator for the island's management, before he was allowed to visit the mainland for a short time every day and set free. But these days, Sentosa is a popular resort island, with numerous beaches, hotels and restaurants, and attracts around 19 million visitors every year. Advertisement

Trump said Thursday when it's all said and done he expects the normalization of relations between the U.S. and North Korea. He floated a peace agreement as a potential show of good faith.

'We're looking at it. We're talking about it with them. We're talking about it with a lot of other people. But that could happen,' he said at his news conference on Thursday. 'Sounds a little bit strange, but that's probably the easy part; the hard part remains after that.'

Klingner, an ex-CIA operative who is now a senior fellow at the conservative Heritage Foundation, cautioned Trump against being too ready to sign an agreement, even one as benign on the surface as declaring peace, however.

'Even if just a political declaration is made, that could have an impact on alliance deterrence capabilities, which would be dangerous if we don't first address the North Koran threat,' he told DailyMail.

He said any deal that Trump signs must include 'a clear commitment to denculearization' based on the United Nations' standards, not North Korea's, and it must include 'sufficient verification' that Kim has given up all of his nuclear weapons and production facilities.

Beatrice Finh, the executive director of The International Campaign to Abolish Nuclear Weapons (ICAN), similarly said that a deal must include a timeline for disarmament and a requirement that competent international authorities carry out routine compliance checks.

Finh said mandatory adoption of the Comprehensive Test-Ban Treaty by both North Korea and the United States, which is a signatory to the UN-treaty but hasn't ratified it, should also be part of any accord that comes about.

'We need to see the international legal framework involved in this deal, not just whatever these two men like that come up with,' she stressed.

In 2017, Finh accepted a Nobel Peace Prize on behalf of ICAN for the organization's work to implement the test ban treaty.

She assessed ahead of Trump's meeting with Kim, 'There are no quick fixes to this. This is going to be a long process.

'Going to war is not an option, so we need to work together,' she said, ' and that's also why it important to bring in the international community and the legal framework that exists to build a kind of consistent stable ground for disarming nuclear weapons.'

A sign for a police checkpoint is newly set up in front of the Capella Hotel in Singapore, where Trump and Kim will meet

The potential for a 'bad deal' that leaves America's allies in the region at risk was an issue uniting the left and the right heading into the summit.

Schumer led a group of seven Senate Democrats in sending a letter to Trump last week stipulating what it would take for him to receive support for a deal in the split party Senate.

They want a permanent ban on nuclear weapons, as well as language barring North Korean from further developing ballistic missiles.

'If President Trump meets with Kim Jong-un and receives a deal that truly lives up to these principles, he will have made the world a much safer place,' Schumer said during a call with reporters. 'But if he tries to reach a deal with Kim Jong-un, just for the sake of reaching a deal, and the agreement fails to live up to the principles we've laid out, then he'll have been bested at the negotiating table yet again.'

While Trump has not explicitly said that a deal with North Korea would have to include the demands made by Senate Democrats, he lodged a nearly identical list of complaints against the Iran nuclear deal that was brokered by the previous administration.

Trump has since ended U.S. involvement in the nuclear accord on the grounds that it had a 10-year sunset clause for some operations and did not punish Tehran for the development of ballistic missiles.

He did not comment on the issue of ballistic missiles on Thursday in the Rose Garden as a dispute over short- and long-range missiles came up several times during a joint news conference with Japan's Abe.

Instead, it was the Japanese prime minister who said, 'On this point, between Japan and U.S. and international community share the same view. I am convinced about it.'

As a neighbor to North Korea, Japan is asserting that a deal must ban all ranges of ballistic missiles and weapons of mass destruction and not just the ones with the ability to cross the Pacific to hit targets in the continental U.S.

Trump said Thursday that he was taking into consideration the concerns of all the major players in the region as he sits down with Kim to make a deal – such as South Korea's Moon Jae-in and China's Xi Jingping.

'President Xi of China has been terrific. The border has been certainly more closed than ever before. I'd like them to close it a little bit more, but it's been more closed than ever before,' Trump said of the leader who has become an unlikely friend of his. 'I give President Xi tremendous credit, and I give President Moon tremendous credit. He really would like to see something happen.'

He added, 'They've been living with the threat of war from their beginning, and it doesn't make sense. And I really believe that Kim Jong-un wants to do something. I think he wants to see something incredible happen for the people of North Korea.'

The pressure is on for Trump to come out of the summit with something tangible, even if his administration says that's not the point of the two-party talks - especially in the context of Trump's recent decision to withdraw the U.S. from the nuclear accord it entered into in 2015 with Iran, says Joel Rubin, a former deputy assistant secretary of state for legislative affairs who is an adjunct faculty member at Carnegie Mellon.

'He can't come back from [talks with] North Korea with an agreement that's three pages after having just ripped up a several hundred page detailed document with Iran and have it pass the laugh test,' Rubin told DailyMail.com.

The Iran deal, he noted, was the product of years of negotiations.

'So for the president to go to a summit first, is not how it's typically done. It's usually done after most of these issues have been hammered out and there's clarity on the objectives,' he said. 'They want to do it differently, so, OK, good, let them him do it differently, and I think there's value in having him engage.

'But he needs to stay engaged and he needs to find what they want in order for it to really be an effective negotiation,' Rubin said.

Trump is seen departing Canada for Singapore on Saturday morning local time after leaving the G7 summit early amid a spat with Canada and France