ANKARA, Turkey - Turkey's prime minister asked U.S. President Barack Obama on Monday to prevent a possible House vote on a resolution declaring the World War I-era killings of Armenians a genocide.

Foreign Minister Ahmet Davutoglu told parliament that Prime Minister Recep Tayyip Erdogan had sent Obama a letter asking he prevent the vote, saying it could damage ties between the two allies.

"We cannot allow the resolution to hang over Turkish-U.S. ties like a Sword of Damocles," Davutoglu said.

A vote could take place before Democrats hand over leadership of the House to Republicans next month.

Government spokesman and State Minister Cemil Cicek said Turkey is bothered that the issue has not disappeared from the agenda for good. He stressed, however, that good relations with the U.S. were important, despite some ups and downs.

"We are disturbed that this issue comes to the agenda every year," Cicek said. "We don't find it right that this is used as a torture tool over us."

Historians estimate up to 1.5 million Armenians were killed by Ottoman Turks around the time of World War I. Turkey denies the deaths constituted genocide.