Trump and Turkish President Recep Tayyip Erdogan are expected to address the Syrian civil war, the refugee crisis and the fight against the Islamic State group.
Shortly after Erdogan arrived in Washington, Turkish Prime Minister Binali Yildirim told his party members that U.S. cooperation with Syrian Kurds "is not something acceptable" for Turkey.
Turkey is determined to "root out terror," Yildirim said, if "necessary guarantees for Turkey's sensitivities and issues pertaining to Turkey's security are still not given."
The Trump administration has ramped up efforts to respond to the crisis in Syria, taking unprecedented action against Syrian President Bashar Assad's government over its use of chemical weapons against civilians.
But with Iran and Russia working to bolster Assad's government, the Trump administration is turning to regional allies, including Turkey, Saudi Arabia and Egypt for help as it crafts its Syria policy.
Complicating that effort, however, was an announcement by the Trump administration that it plans to arm Kurdish Syrian fighters in the fight against the Islamic State group. Turkey has been pressuring the U.S. to drop support for the Kurdish militants in Syria for years and doesn't want them spearheading the Raqqa effort.
Turkey believes they're linked to a Turkish Kurdish group, known as the PKK, which the U.S., the European Union and Turkey all consider a terrorist organization.
Trump's deal-making skills will be put to the test as he works to assure Erdogan that the decision to arm Kurdish fighters in Syria will not result in weapons falling into the wrong hands.
Erdogan arrived Monday in Washington, the Turkish flag hanging prominently outside the Blair House, a historic presidential guesthouse across the street from the White House.
The meeting is considered high stakes for the nascent Trump administration as it looks to engage regional allies in delicate security matters while enforcing international standards for human rights.
Trump's willingness to partner with authoritarian rulers and overlook their shortcomings on democracy and human rights has alarmed U.S. lawmakers of both parties. That puts added pressure on him to get results.
Trump has gone out of his way to foster a good relationship with Erdogan. After a national referendum last month that strengthened Erdogan's presidential powers, European leaders and rights advocates criticized Turkey for moving closer toward autocratic rule. Trump congratulated Erdogan.
But Erdogan may not be amenable to accepting the U.S. military support for the Kurds in a quid pro quo. Last month, the Turkish military bombed Kurdish forces in Syria and Iraq, in one case with American forces only about six miles (10 kilometers) away. His government has insisted it may attack Syrian Kurdish fighters again. The U.S., whose forces are sometimes embedded with the Kurds, has much to fear.
Washington is concerned by rising anti-Americanism in Turkey that Erdogan's government has tolerated since the July coup attempt. The U.S. also has pressed unsuccessfully for the release of Andrew Brunson, an American pastor, and other detained U.S. citizens.
