South Carolina Republican Sen. Lindsey Graham ripped into Turkish President Recep Tayyip Erdogan during a tense Oval Office meeting Wednesday over the country’s invasion of Syria and attacks on America's Kurdish allies, according to aides and the senator himself, reports FoxNews, citing the senator and his aides.

While in Washington, Erdogan met with President Trump and several Republican senators at the White House. Fox News is told there were “a lot of people with a lot of gripes” during the meeting. At one point, according to aides, Graham “called Erdogan out on his B.S. that Turkey has been fighting ISIS.” While all the senators expressed their issues with Erdogan, Graham was said to be “on the more aggressive side.”

According to sources, Graham told Erdogan, “You have done something no one thought was possible. You have united the US … against [Turkey].”

Having senators in an Oval Office meeting between the president and a foreign leader is highly unusual.

Congressional aides said that the White House wanted Erdogan to hear directly from the senators about their concerns. It was described as a “good cop, bad cop” scenario, where Trump played the part of the “neutral” cop, while senators got into it with Erdogan. One aide said that “Graham was the worst cop of all.”

Erdogan pulled out his iPad to show the senators a propaganda video depicting the Kurds as terrorists. On Thursday, Graham confirmed the video incident and said he asked Erdogan, "Do you want me to get the Kurds to play a video about what your forces have done?"

He said he was especially infuriated by Erdogan's claim to have done the heavy lifting in the battle against ISIS, considering all the casualties sustained by Kurdish forces.

His words failed to placate members of Congress and others who accuse Turkish-backed forces of killing Kurdish civilians and causing a humanitarian crisis in the incursion, which prompted the U.S. last month to hurriedly evacuate a small number of American troops from near the Syria-Turkey border.

“While our alliance with Turkey is important to maintaining U.S. national security interests, Turkey's assault against our Kurdish allies, who have a long history of standing with America against our enemies, is absolutely unacceptable,” said Texas Sen. Ted Cruz, another senator in attendance, in a statement after the meeting.