A defiant Donald Trump told a giant swell of fans Wednesday night in Phoenix that he will build his famed border wall, and reiterated that Mexico will foot the bill.

'We will build a great wall along the southern border. And Mexico will pay for the wall. One hundred percent,' Trump said.

'They don't know it yet, but they're going to pay for it.'

Trump met Wednesday afternoon with Mexican president Enrique Peña Nieto, and praised him in Phoenix as 'wonderful.' But he held firm on sending Mexico City a bill for the wall's construction.

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A defiant Donald Trump told a giant swell of fans Wednesday night in Phoenix that he will build his famed border wall, and reiterated that Mexico will foot the bill

'We will build a great wall along the southern border. And Mexico will pay for the wall. Hundred percent,' Trump said

'They're great people, great leaders, but they're going to pay for the wall.'

'On day one, we will begin working on an impenetrable, physical, tall, powerful, beautiful southern wall,' Trump boasted.

He pledged to employ technologies to harden the barrier, including 'above and below ground sensors' along with 'towers, aerial surveillance and manpower.'

This, he said, would 'supplement the wall, find and dislocate tunnels and keep out criminal cartels.'

Trump said that after meeting with Nieto, he trusts 'Mexico will work with us. I really believe it.'

'They will work with us, they really will. They want to solve this problem with us,' he said of the drugs, guns, money and illegal immigrants who cross the border every day.

He pledged to employ technologies to harden the barrier both above and below ground, including 'towers, aerial surveillance and manpower.'

Trump's speech came just a short time after Mexican President Enrique Peña Nieto directly challenged Trump after his historic visit to Mexico City on Wednesday, insisting he had told the Republican that his country will not pay for a wall along the border.

Trump had told reporters earlier in the day that the pair agreed America had a right to wall off its 2,000-mile southern border, but claimed 'we didn't discuss' who would fund it.

Nieto later tweeted in Spanish: 'From the start of the conversation, I made it clear Mexico will not pay for that wall.'

He added that they addressed other issues during the rest of their conversation, and their meeting was 'respectful.'

Nieto spokesman Eduardo Sánchez told a Wall Street Journal reporter that Trump had told the truth – because the Mexican president had made a defiant statement but the American never responded.

'Mr. Trump was not lying... because there was no discussion,' Sánchez said.

TRUMP'S GRAND PLAN TO DEAL WITH IMMIGRATION Donald Trump outlined an aggressive plan to deal with America's swelling illegal-immigrant ranks, telling a Phoenix crowd that he would take specific steps if he were president. 1. Trump's signature issue: 'We will build a great wall along the southern border. And Mexico will pay for the wall.' 2. A pledge to begin deporting more border-crossers instead of engaging them in long, drawn-out legal proceedings: 'We're going to end catch-and-release.' 3. 'Zero tolerance for criminal aliens,' and a promise to deport 'illegal immigrants who are arrested for any crime whatsoever.' 4. Trump would 'block funding for sanctuary cities' that refuse to turn over criminal aliens to the federal government for deportation. 5. 'Cancel unconstitutional executive orders' – a code for President Obama's 'deferred action' orders that protect an estimated 5 million illegal immigrants and their family members from deportation. 6. Trump would 'suspend the issuance of visas' to people from countries 'where adequate screening cannot occur,' including 'places like Syria and Libya.' 7. Unspecified action against the 23 countries that refuse to accept their own citizens after the U.S. deports them. 8. A 'biometric entry-exit visa tracking system' like one that Congress has demanded, a system that would help authorities identify and remove the half-million visa holders who stay longer than allowed each year. 9. A strict use of the 'e-verify' employment system in order to 'turn off the jobs and benefits magnet' that lures foreigners into the U.S. 10. The formation of an 'immigration commission' that would change the criteria for entering the U.S., selecting immigrants 'based on their likelihood of success in U.S. society, and their ability to be financially self-sufficient.' Advertisement

He hugged them as they walked up to the lectern and told the stories about how their children died at the hands of immigrants

Trump shares the stage with parents whose family members were killed by undocumented immigrants during his speech

LAYING THE FOUNDATION: Donald Trump described five 'shared goals' after his meeting Wednesday with Mexican President Enrique Peña Nieto, including the recognition that America has the right to build 'a physical barrier' on its southern border

STANDOFF? Trump initially said the pair had not discussed who would pay for the wall, but Nieto later said his country would not be providing funding

ESPERA UN MINUTO! Nieto said on Twitter hours later that he had insisted Mexico would never pay for the wall, although Trump told reporters they 'didn't discuss' that topic

ART OF THE DEAL: Trump initially said he and Nieto 'didn't discuss' who would pay for his wall's construction, despite pledging repeatedly that Mexico would pick up the check – but Nieto later disputed that and said he made it clear funding was a nonstarter

Trump's campaign released a statement in response to Nieto's tweet, insisting it was 'unsurprising' Nieto and Trump had 'different views' on the issue – but not addressing the embarrassment of being called a liar on the world stage.

Jason Miller, Trump's senior communications adviser, called the Mexico meeting 'the first part of the discussion and a relationship builder between Mr.Trump and President Pena Nieto.'

'It was not a negotiation, and that would have been inappropriate. It is unsurprising that they would hold two different views on the issue, and we look forward to continuing the conversation.'

Nieto spokesman Eduardo Sanchez told Reuters that his boss had said 'that Mexico, as he has said on several occasions ... will not pay for that wall.'

Hillary Clinton campaign chairman John Podesta mocked Trump over Nieto's tweeted protest.

'It turns out Trump didn't just choke, he got beat in the room and lied about it,' Podesta said in a statement.

'Donald Trump has made his outlandish policy of forcing Mexico to pay for his giant wall the centerpiece of his campaign. But at the first opportunity to make good on his offensive campaign promises, Trump choked.'

NOT LYING: Wall Street Journal Reporter David Luhnow interviewed Nieto's spokesman, who spelled out how the landmark meeting began

Trump earlier stated he and Nieto had agreed the United States had a right to build a wall along the border with their southern neighbor – something Nieto never disputed.

'Having a secure border is a sovereign right and mutually beneficial,' Trump told reporters in Mexico City, listing the second of what he called 'five shared goals.'

'We recognize and respect the right of either country to build a physical barrier or wall on any of its borders to stop the illegal movement of people, drugs and weapons.'

'Cooperation toward achieving this shared objective – and it will be shared – of safety for all citizens, is paramount for both the United States and to Mexico,' Trump said.

MUY AMIGABLE: Trump and Nieto met in private for more than an hour before addressing reporters in a format that elevated the Republican candidate to the level of a world leader

OLD GLORY AWOL: No American flag was present for the remarks, a sign of the protocol reflecting Trump's status as a candidate rather than a representative of the U.S. government

In taking only a few questions from journalists, Trump boasted that Nieto agrees the idea of an impenetrable border wall – long the hallmark of his unconventional candidacy for the White House – is in the best interest of both nations.

'We want what's good for the United States and the president wants what's good for Mexico,' Trump said.

'We both realized from the beginning that it's good for both of us, better for both of us.'

Initially it was reported that the two men did not discuss whether Mexico would pay for the wall's construction, as feature of Trump's plan that he has insisted he can deliver.

'We didn't discuss that. Who pays for the wall? We didn't discuss,' Trump said.

Nieto did not directly address the question of a border wall, but let Trump articulate the 'five shared goals' without him – including 'ending illegal immigration' and 'dismantling drug cartels' and 'improving' the North American Free Trade Agreement.

The Mexican president did smooth the waters between Trump and Mexico's citizens, however.

'Mexicans have felt offended by what has been said,' Nieto declared, referring to some of Trump's heated rhetoric.

'But I am certain that his genuine interest is in building a relationship that will provide our mutual societies improved well-being.'

The two men spoke against a backdrop that featured a Mexican flag but no American flag, an nod to the fact that Trump does not represent the United States and is only a candidate for the presidency.

WHAT TRUMP HAS SAID ABOUT THE WALL IN THE PAST TRUMP SAID GETTING MEXICO TO PAY FOR THE WALL WOULD BE 'EASY' Trump Campaign Rally, Fredericksburg, Virginia, August 20, 2016 'We're going to build the wall and Mexico is going to pay for the wall, believe me, one hundred percent. Believe me. 'That'll be very easy. That will be very, very easy. Politicians think we're joking, we don't joke. We don't joke. This is a movement. This is a movement, and movements don't joke. 'Believe me. It's getting worse now as thousands of recent border crossers are being relocated to the State of Virginia, and you don't know who they are, you don't know where they come from.' LA Times, August 22, 2016 Trump assured the crowd that he would seal the southern border, a plan that is popular among his overwhelmingly white loyalists but offensive to many Latinos and Asians whose votes he needs in Colorado, Nevada and Florida. 'Don't worry. We're going to build the wall,' he said. 'That wall will go up so fast, your head will spin. And you'll say, 'You know, he meant it.' And you know what else I mean? Mexico is going to pay for the wall.' TRUMP WAS WILLING TO START A TRADE WAR WITH MEXICO OVER PAYING FOR THE WALL Primary debate - Houston, Texas, February 2, 2016 CNN host Wolf Blitzer: 'If the -- if the Mexicans don't pay for the wall, will you start a trade war with Mexico?' Trump: 'Well, you know, I don't mind trade wars when we're losing $58 billion a year, you want to know the truth. We're losing so much. We're losing so much with Mexico and China -- with China, we're losing $500 billion a year. 'And then people say, 'don't we want to trade?' I don't mind trading, but I don't want to lose $500 billion. I don't want to lose $58 billion.' MSNBC Town Hall, Green Bay, Wisconsin, March 30, 2016 Trump: 'We have a trade deficit with Mexico, $58 billion a year. The wall is going to cost approximately $10 billion. Believe me, they will pay in one form or another--' MSNBC host Chris Matthews: 'If not -- or else what?... So we cut off Japan, we cut off -- this is the -- this is your strategy in every case. We could walk, no more trade with Mexico.' Trump: 'You have to always-- Oh, absolutely.' Matthews: 'No more troops in Europe.' Trump: 'And by the way, when I say no more trade, once you -- once they know that you are really willing to go that extra length, there will always be trade, but we'll make good deals. We're making the worst trade deals.' Matthews: 'Yeah, but the bottom line is always we walk.' Trump: 'You have to be able to walk, yes. It's unlikely that you'll have to, but you have to be able to walk.' TRUMP HAS SUGGESTED TENSIONS WITH MEXICO OVER PAYING FOR THE WALL COULD BECOME PHYSICAL Morning Joe, MSNBC, March 9, 2016 Co-host Bob Woodward (journalist for the Washington Post): 'If they (Mexico) say no, would you be willing to go to war to make sure we get the money to pay for this wall?' Trump: 'Trust me, Bob, when I rejuvenate our military, Mexico's not going to be playing with us with war, that I can tell you. Mexico isn't playing with us with war. Look, I have great relationships with the Mexican people. 'Look, you can see I'm winning every single poll in these primaries when they go out, when the polls come back with Hispanics. 'I have thousands of Hispanics that work for me and tens of thousands that have worked for me over the years.' (Source: Hillary for America and various reports) Advertisement

BIENVENIDO!: Nieto invited Trump last Friday to visit him and has extended the same offer to Democratic rival Hillary Clinton

But in most other respects Nieto treated him as an equal, acknowledging that the North American Free Trade Agreement – Trump's secondary beef with Mexico – could benefit from renegotiation.

'As partners we have to work together in order to avoid the loss of jobs from our region,' Nieto said. 'However, this does not mean that the North American Free Trade Agreement can't be improved to the benefit of both parties. It is an agreement that was signed over 22 years ago.'

Trump landed in Mexico City just a few hours earlier for the unusual bilateral meeting with Nieto – his first sit-down with a foreign leader since he launched his campaign last year.

Only a handful of protesters turned up downtown near the presidential palace in advance of the historic meeting. And only a small contingent of foreign reporters and photographers were there to see it.

Trump's campaign left the traveling press corps in Phoenix, where they arrived late Tuesday night in advance of a promised landmark speech Wednesday evening on the hot-button topic of immigration.

Even a press pool reporter from DailyMail.com, designated to travel with the candidate for the trip, was not granted access to accompany the campaign.

BLACKOUT: Donald Trump's secretive Mexico City arrival on Wednesday was not witnessed by his press corps, who were left stranded in Phoenix, Arizona after his campaign refused to allow them to travel with him – and photo editors distributing helicopter images cautioned that Trump may not have been aboard

HISTORIC VISIT: Trump is meeting with President Enrique Peña Nieto, irking some who are angry at the billionaire for clobbering Mexico during his 14-month-long White House run

The press charter plane was available, according to a person with knowledge of the aircraft's operations, but the campaign decided not to clear it for flight.

Trump risked a backlash from Nieto after he returns to the U.S. Nieto had previously compared Trump's political rise to the early public enthusiasm shown for murderous dictators Adolph Hitler and Benito Mussolini.

But the Republican presidential nominee caught only respect from the Mexican leader, and enjoyed a formal setting usually only aforded to heads of state.

The high-risk-high-reward gambit will be closely watched by Hispanic American voters who are looking for signs that Trump is softening his threats to deport millions of people in the country illegally.

MUY TRANQUILO: Only a handful of protesters showed up to hammer Trump in Mexico City

With Trump's regular cadre of Trump reporters stranded two time zones away, the arrival of Trump's aircraft wasn't caught on camera.

The Associated Press was only able to confirm the plane's touchdown from an airport source who wasn't authorized to speak on the record.

And still photographs from wire services, showing a helicopter believed to be carrying Trump, known to Secret Service agents by the code name 'Mogul,' carried a disclaimer that they 'allegedly' showed Trump in the air.

Hillary Clinton attacked Trump Wednesday morning in a speech to the American Legion convention in Cincinnati, Ohio, a meeting Trump will address Thursday.

'Dropping in on our neighbors for a few hours and then flying home again,' Clinton claimed, won't make up for 'a year of insults and insinuations.'