Trump elaborated on his conversation with Erdoğan during another bilateral meeting in Watford with German Chancellor Angela Merkel.

“We discussed Syria. We discussed the Kurds. We discussed numerous things, and we're getting along very well,” he said.

“The border and the safe zone is working out very well ... and I gave a lot of credit to Turkey for that," the president continued. “The cease-fire is holding very much so, and I think people are surprised, and maybe some day they'll give me credit, but probably not.”

Trump granted tacit approval for Turkey’s incursion into northern Syria in October — which resulted in the slaughter of U.S.-allied Kurdish fighters — and withdrew the last American forces from that area of Syria while maintaining a troop presence to safeguard the Middle Eastern nation’s lucrative oil fields.

“We pulled our soldiers out, we took over the oil. We have soldiers where the oil is, and that's the way I like it," Trump said, adding that the Syria-Turkey border has “been under siege for many, many decades, and it was time for us to leave.”

Trump's remarks come after a suspected Syrian government airstrike killed 13 civilians Monday in a northwestern rebel-held city, and Turkish artillery shells killed at least nine more in a Kurdish-held town, according to the Associated Press.

The surprise session Wednesday between the American and Turkish presidents is likely to draw attention from other world leaders who are in London this week to attend the western military alliance’s annual meeting.

Some of those government heads, as well as congressional Republicans back in the United States, have been outspoken in their criticism of the assault by Erdoğan’s military.

During a testy exchange with Trump on Tuesday, French President Emmanuel Macron rebuked U.S. diplomacy in the region and denounced the Turkish invasion.

“When I look at Turkey, they now are fighting against those who fight with us — who fought with us shoulder-to-shoulder against ISIS — and sometimes they work with ISIS proxies,” he said.