WASHINGTON — President Trump is to meet at the White House on Tuesday with President Recep Tayyip Erdogan of Turkey, embracing a leader whose authoritarian crackdown he has praised even during mounting tensions between the United States and Turkey, a crucial NATO ally.

The meeting provided an opportunity for Mr. Trump to confer with Mr. Erdogan as the two are at odds over his administration’s move to give weapons to the Y.P.G., a Kurdish militia fighting alongside Syrian Arab forces against the Islamic State, and its refusal to arrest or extradite Fethullah Gulen, a Turkish cleric living in Pennsylvania whom Mr. Erdogan has accused of orchestrating a coup attempt against him last July.

Despite the divisions, Mr. Trump has signaled warm support for Mr. Erdogan far beyond that afforded him by former President Barack Obama, with whom he had a chilly — if businesslike — relationship. Last month, Mr. Trump telephoned Mr. Erdogan to congratulate him on winning a much-disputed referendum that cemented…