A meeting between U.S. President Joe Biden and Turkish President Recep Tayyip Erdogan later this month is under discussion, a senior Turkish official said on Friday, with Turkey-Russia relations, U.S. weapons, and conflicts in Ukraine and Syria on the agenda, Reuters reported.

Erdogan is expected to visit Washington D.C., from September 17 to 22.

Biden and Erdogan last met in late June on the sidelines of a NATO summit in Madrid, where Turkey lifted its veto on Finland and Sweden joining the pact despite fierce opposition to their membership from Russia.

At the end of that summit Biden said the United States supported the sale of F-16 fighter jets to Turkey, and that he was confident the congressional approval needed for the sale can be obtained.

Discussions between the two leaders would include the war in Ukraine, relations between Turkey and Russia, and the Ukraine grain export deal, the Turkish official said.

Sentiment toward Turkey in the U.S. Congress has turned sour over the past few years after Ankara acquired Russian-made defense missile systems, triggering U.S. sanctions as well as Turkey's removal from the F-35 fighter jet program.