ANKARA, October 16 (RIA Novosti) - A resolution passed by a U.S. House committee last week classing the 1915 massacre of Armenians as genocide will harm relations with Turkey, the country's premier said Tuesday.

Last Wednesday the U.S. House of Representatives Foreign Affairs Committee passed the document despite opposition from President George W. Bush. Turkey is a key NATO ally and a crucial U.S. partner in Iraq operations.

"The Turkish people are on the verge of losing their patience over this issue," Turkish Prime Minister Recep Tayyip Erdogan said. "If Turkey incurs losses from this, then our opponents will lose ten times as much. Everyone should realize this."

Ankara insists that the deaths and deportations of Armenians at the end of the Ottoman period were caused by civil war rather than deliberate genocide. However, the majority of Western academics qualify the massacre as genocide.

"We have forgotten nothing and have nothing to be ashamed of in the face of history. We have opened up our archives. Let Armenia do the same," the premier said, adding that investigation of the tragic events must be left to historians, not politicians.

Turkish NTV television channel said on Monday that Turkey might restrict U.S. use of a joint air base in Incirlik, close off its air space to U.S. warplanes, and ban Armenian aircraft from flying over its territory. The majority of supplies for U.S. troops in Iraq, including fuel and military hardware, pass through Turkey.

Ankara previously froze military cooperation with France after its parliamentarians passed a similar resolution.