Donald Trump launched a new defense of his pullout of American forces from northern Syria Wednesday, saying the situation is 'strategically brilliant for the U.S.' and dismissing the Kurds as 'no angels.'

At a White House press conference Wednesday, Trump welcomed further Russian military intervention in Syria, as Moscow teams with Syrian dictator Bashar al-Assad and U.S. rival Iran to counter Turkey's attack on Kurds in Syrian territory – a conflagration about which Trump proclaimed 'Welcome to it.'

The president attacked U.S. allied Kurdish fighters as 'no angels,' and described them as a mercenary force, even as critics from both parties lamented a policy shift as leaving them victim to slaughter at the hands of the Turks.

'Syria has a relationship with the Kurds – who by the way are not angels,' Trump told reporters alongside Italian President Sergio Mattarella. 'Who is an Angel? There aren't too many around. But Syria has a relationship with the Kurds. So they'll come in for their border. And they'll fight,' Trump said.

UNDER CONTROL: President Donald Trump welcomed Russian intervention along with Syria to push back against Turkey's incursion into Syrian territory. Of the overall conflict, he said: 'It's a very semi-complicated – not too complicated if you're smart – but it's a semi-complicated problem, and I think it's a problem that we have nicely under control'

'They may bring partners in, they could bring Russia in. And I say welcome to it,' Trump continued, after earlier in the day comparing the area to 'a lot of sand' that various sides can play with.

Trump then cast Syria as a potential quagmire for Russia – but also called Moscow's stepping in the the place of the U.S. to assist the Kurds as a 'good thing.'

'Russia went into Afghanistan. When it was the Soviet Union and it became Russia. It became a much smaller country because of Afghanistan. You can overextend,' Trump observed.

'You can do a lot of things. But frankly, if Russia's going to help in protecting the Kurds that's a good thing, not a bad thing. But it would be led by Syria. And Syria doesn't want Turkey to take its land. I can understand that. But what does that have to do with the United States of America?'

'They're fighting over Syria's land. Are we're supposed to fight a NATO member in order that Syria who is not our friend – keeps their land? I don't think so. But Syria does have a relationship with the Kurds,' Trump said.

Trump was non-plussed about a problem that has vexed policymakers but that he described as 'semi-complicated.'

'So it's a very semi-complicated – not too complicated if you're smart – but it's a semi-complicated problem, and I think it's a problem that we have nicely under control,' Trump said.

'Turkey and Syria will hopefully work it out between themselves. Hopefully ISIS will be guarded,' Trump said, in reference to ISIS prisoners captured after a multi-year struggle.

Speaking earlier in the Oval Office, he said the invasion of northern Syria by Turkey's military was 'not our problem' and claimed: 'The Kurds are much safer right now.'

He was dismissive of Kurdish desires for a protected homeland, and said the Kurdistan Workers Party, the PKK, was 'worse at terror and more of a terrorist threat' than ISIS. Turkey has long feared establishment of Turkish-controlled territory on its border out of concerns it could lead to domestic unrest.

'We have one country that wants land perhaps that doesn't belong to them because they want a 22-mile strip of they call it freedom, call it a lot of things,' Trump said. 'They want to get terrorists out. You have another country that says, you can't have our land and they're going to have to work that out.'

Despite sending his vice president Mike Pence and Secretary of State Mike Pompeo to Ankara to hold urgent talks with Turkish president Recep Tayyip Erdogan on a ceasefire, Trump described the fighting in northern Syria as 'not our problem.'

He also indicated there may be a one-day delay in Pence's trip, after Turkish President Recep Erdogan said he wouldn't meet with Pence, only Trump.

'He'll be leaving either late tonight or tomorrow. And he was going to leave yesterday but they have to have certain security done, he's a very important man in our country,' Trump said.

Trump took a similar tone in remarks in the Oval Office earlier Wednesday.

'If Turkey goes into Syria it is between Turkey and Syria. It's not our problem,' he said.

'Syria's friendly with the Kurds. The Kurds are very well protected. Plus, they know how to fight. And, by the way, they're no angels.'

As bombing and shelling continued in northern Syria, he said: 'I view the situation on the Turkish border with Syria to be, for the United States, strategically brilliant.

'All American soldiers are away from the site.' He added: 'They shouldn't be [there] as two countries fight over land.'

In fact U.S. ground forces still present in northern Syria had called in attack helicopters are strike fighters in a show of force on Tuesday to prevent Turkish-backed forces approaching their position.

And Trump also threw ceasefire talks into confusion he said: 'Syria and Turkey can fight. They've got a lot of sand over there. There's a lot of sand that they can play with.'

Almost immediately he faced a Republican backlash, with Lindsey Graham warning he risked 'disaster worse than President Obama’s decision to leave Iraq,' and adding: 'I fear this is a complete and utter national security disaster in the making and I hope President Trump will adjust his thinking.'

'If Turkey goes into Syria it is between Turkey and Syria. It's not our problem,' Trump said in the Oval Office

The Syrian town of Ras al-Ain was seen being bombarded on the eighth day of Turkey's military operation against Kurdish forces

Russia has so far proved the most effective peacekeeper in Syria, after brokering a deal between the Kurds and Syrian government forces that has seen Assad's troops move to the front line (red arrows). Vladimir Putin has also positioned his troops between Turkey and government forces around Manbij, stopping an anticipated attack

Turkey launched a military operation against Kurdish fighters allied with the United States after Trump pulled troops from the region earlier this month.

His decision was strongly condemned in the U.S. - including by usual Republican allies in Congress - and around the world as contributing to regional instability and the abandonment of an ally.

He noted that Syria was getting 'some help with Russia and that's fine.'

'If Russia wants to get involved with Syria, that's really up to them,' he said. 'It's not our border. We shouldn't be losing lives over it.'

Trump also suggested the Kurds had intentionally allowed some ISIS prisoners to escape prisons where they were being held. A U.S. attempt to remove the 50 prisoners the most dangerous failed when American troops had to withdraw more quickly.

'Some were released just for effect to make us look a little bit like "oh gee, we have to get right back in there,"' he said.

All-out attack: Lindsey Graham unloaded on Trump within minutes of his Oval Office outburst

'You have a lot of countries over there that have power and that hate ISIS very much, as much as we do.'

Among those who 'hate' ISIS more than the U.S., he suggested, were Russia.

Italy's president, Sergio Mattarella, sat impassively beside Trump as he defended his actions.

The U.S. president spoke as the Syrian town of Ras al-Ain was seen coming being bombarded on the eighth day of Turkey's military operation against Kurdish forces - and as Erdogan scoffed about the U.S. peace delegation saying he had no intention of implementing a ceasefire.

Intense fighting continued Wednesday around the border towns of Tel Abaid and Ras al-Ain, while Russian and Syrian government troops - which took control of Manbij on Tuesday - moved up to the outskirts of Kobane, another key crossing point.

Erdogan, speaking to reporters in the Turkish parliament earlier on Wednesday, said he was reevaluating his planned visit to Washington in November - where Trump had invited him to the White House but may visit Russia.

At the White House, Trump's latest public pronouncement only added to confusion over Pence and Pompeo's mission in Turkey.

Pence said he was seeking a ceasefire on Trump's orders, but by describing it as 'not our problem,' Trump appeared to publicly countermand that.

And Erdogan said Wednesday that he will refuse to meet with U.S. National Security Advisor Robert O'Brien and his delegation when he arrives later in the day to discuss his country's invasion of Syria.

'I am not going to talk to them. They will be talking to their counterparts. When Trump comes here I will be talking to him,' Recep Tayyip Erdogan told reporters at the Turkish parliament.

O'Brien flew to Ankara as an emergency measure to try to stave off an escalation of Turkey's attacks on Syrian Kurds.

Pence and Pompeo are due to arrive Thursday. Initial media reports described Erdogan saying he would refuse to meet with them. Those turned out to be incorrect, according to a transcript released by Turkey's presidential communications office.

Pompeo said Wednesday during a Fox Business Network interview that he has 'every expectation' he and Pence will meet with Erdogan.

Erdogan did say, however, that he may re-evaluate whether to visit the White House on November 13.

Trump extended the invitation this month, but the Turkish leader complained Wednesday that 'arguments, debates, conversations being held in Congress regarding my person, my family and my minister friends are a very big disrespect.'

'I am not going to talk to them. They will be talking to their counterparts. When Trump comes here I will be talking to him,' Recep Tayyip Erdogan told reporters at the Turkish parliament, spaking about a delegation led by the U.S. national security adviser

Thousands of civilians have been fleeing the Kurdish-held town of Kobani ahead of the imminent arrival of Turkish troops

These Syrian government forces were gathering at Tabqa airbase near Raqqa, northern Syria. It was formerly in U.S. hands

The move to come up with a sanctions package was pushed by Democratic Speaker Nancy Pelosi and Lindsey Graham, the Republican senator who has publicly split from his golf companion Trump over the troop pullout.

The sanctions being suggested by Congress appear to go far further than those threatened by Trump, who signed an executive order last week giving him power to impose new tariffs on Turkish steel and a range of other measures.

In Turkey the sanctions have been meet with scorn.

Turkey's foreign minister said Wednesday that the country will retaliate against U.S. sanctions with measures of its own, but did not specify what these would be.

Mevlut Cavusoglu told parliament that the current US position towards Turkey is at a 'critical juncture' and urged Congress to turn back from its 'damaging approach.'

He added that he will convey the message to Pence, when he arrives on Thursday.

In his interview with the Turkish journalists, Erdogan also shared an anecdote from his telephone call with Trump this week.

'I told Trump: 'You get very angry with the media from time to time. You are now under their influence. Don't listen to them, you are a strong leader. This does not befit a strong leader',' he said.

So far Russia has proved the only effective peacekeeper, after negotiating a defense pact between the Kurds - America's former allies - and the Syrian government.

Putin has also ordered Russian troops to stand between Turkish and Syrian forces around the city of Manbij, halting an anticipated attack on the city.

Even as Erdogan vowed to keep Pence and Pompeo waiting for a meeting with him, the Kremlin announced a summit between the Turkish leader and Putin, scheduled to take place in the coming days.

Moscow said the meeting was to ensure the Turkish operation does not turn into all-out war between Erdogan and Assad's forces.

Earlier on Wednesday, Erdogan vowed to defy calls from Washington to stop the violence, vowing: 'We will never declare a ceasefire.'

He added: 'They [America] are pressuring us to stop the operation. They are announcing sanctions. Our goal is clear. We are not worried about sanctions.'

Russia's presence did not completely prevent the bloodshed, with Erdogan blaming Syrian government forces for a mortar attack which killed one of his soldiers.

Reuters journalists accompanied Syrian government forces who entered the centre of Manbij, a flashpoint where U.S. troops had previously conducted joint patrols with Turkey.

Russian and Syrian flags were flying from a building on the city outskirts and from a convoy of military vehicles.

Russia's Interfax news agency, citing Moscow's Defence Ministry, said later that Syrian forces had taken control of an area of more than 1,000 square km - 386 square miles - around Manbij, including Tabqa military airfield, which had been used by U.S. forces.

During his press conference that the U.S. was fighting 'endless wars' and 'protecting countries that don't even like us.'

'I campaigned on bringing our soldiers back home. That's what i'm doing. Diplomatically it takes a period of time. But, you know, we're in many countries, many countries. I'm embarrassed to tell you how many ... We're protecting countries that don't even like us. They don't even pay us. We're sending additional troops to Saudi Arabia.'

He said he appreciates that Saudi Arabia 'agreed to pay for the cost of deployment and more. Much more.'