U.S. President Donald Trump welcomes Turkey's Pressident Tayyip Erdogan at the White House in Washington, U.S., November 13, 2019. Trump on Wednesday lauded the U.S. relationship with Turkish President Tayyip Erdogan as the leaders started a meeting to overcome mounting differences between the two NATO allies ranging from Syria policy to Turkey's purchase of a Russian missile defense system. REUTERS/Tom Brenner

U.S. President Donald Trump and first lady Melania Trump stand with Turkey's Pressident Tayyip Erdogan and Emine Erdogan upon their arrival at the White House in Washington, U.S., November 13, 2019. Trump's warm welcome of the Turkish president comes amid anger in the U.S. Congress about Ankara's Oct. 9 offensive into Syria to drive out a Kurdish militia, Washington's main partner in the fight against Islamic State. REUTERS/Tom Brenner

U.S. President Donald Trump meets with Turkey's President Tayyip Erdogan in the Oval Office of the White House in Washington, U.S., November 13, 2019. Meanwhile, a protest against Erdogan's visit outside the White House grew heated. Light scuffling broke out as U.S. Park Police on foot and on horses attempted to establish order. REUTERS/Tom Brenner

U.S. President Donald Trump meets with Turkey's President Tayyip Erdogan in the Oval Office of the White House in Washington, U.S., November 13, 2019. Dozens of protesters had gathered outside the White House earlier, waving Kurdish flags and signs labeling Erdogan a "terrorist". They shouted chants such as "Erdogan is ISIS" and "Turkey out of Syria, Turkey out of Kurdistan." REUTERS/Tom Brenner

Turkey's President Tayyip Erdogan listens to an aide as he meets with U.S. President Donald Trump in the Oval Office of the White House in Washington, U.S., November 13, 2019. Washington and Ankara hit a new crisis point last month over Syria, after Erdogan began a cross-border incursion against America's Kurdish allies and upended the U.S. presence there. REUTERS/Tom Brenner

Turkey's President Tayyip Erdogan listens as he meets with U.S. President Donald Trump in the Oval Office of the White House in Washington, U.S., November 13, 2019. Earlier this year, the United States was livid over Turkey's purchase of the Russian missile defense system, which Washington says is not compatible with NATO equipment including its F-35 fighter jet. REUTERS/Tom Brenner