(CNN) US President Donald Trump told Turkish President Recep Tayyip Erdogan the US was "done" with Syria as the pair discussed the possible withdrawal of US forces from the country.
Erdogan was explaining all the problems with the US presence in Iraq and Syria and was irritating Trump, according to a senior administration official who received a detailed readout of the phone call between both presidents.
"OK, it's all yours. We are done," Trump said, according to the source.
Trump announced his decision on Wednesday to withdraw forces from Syria.
Erdogan made his case to Trump during the December 14 call that the US should pull out of Syria by pointing to the near-total defeat of ISIS in the country, according to a separate source familiar with the call. The President then sought assurances from Erdogan that Turkey would continue to fight ISIS and defeat the terrorist group.
A senior White House official said Erdogan gave Trump his "word" that Turkey would finish off ISIS.
"In the call on Friday, Erdogan said to the President, 'In fact, as your friend, I give you my word in this,'" the senior White House official said.
Erdogan, for his part, described his conversation with Trump during a speech last Friday, saying he told Trump that he could clear Syria of ISIS.
"During a conversation I had with Mr. Trump -- he said 'ISIS, can you clear ISIS from this area?'" Erdogan recalled. "We did it before, and we can again as long as we have logistic support from you."
"And so they began pulling out," Erdogan said.
"Within the framework of the phone call we had with Mr. Trump, we have started preparing plans for operations to clear the ISIS elements still within Syria," he continued.
The Associated Press first reported some details of the phone call.
Trump and Erdogan held a phone call again on Sunday where the two discussed the conflict in Syria, both nations said.
"I just had a long and productive call with President @RT_Erdogan of Turkey. We discussed ISIS, our mutual involvement in Syria, & the slow & highly coordinated pullout of U.S. troops from the area. After many years they are coming home. We also discussed heavily expanded Trade," Trump tweeted.