The Bush administration will try to soothe Turkish anger after a House panel's approval of a measure describing as genocide the deaths of hundreds of thousands of Armenians early in the last century.

The House Foreign Affairs Committee defied warnings by President Bush with 27-21 approval Wednesday to send the measure to the full House for a vote. The administration will now try to pressure Democratic leaders not to schedule a vote, though it is expected to pass.

Hours before the vote, Bush and his top two Cabinet members and other senior officials made last-minute appeals to lawmakers to reject the measure.

"Its passage would do great harm to our relations with a key ally in NATO and in the global war on terror," Bush said.

Turkey's President Abdullah Gul criticized the decision to move the measure toward a vote in the House.

"Unfortunately, some politicians in the United States have once again sacrificed important matters to petty domestic politics despite all calls to commonsense," said Gul, according to the state-run news agency Anatolia. "This unacceptable decision by the committee, like its predecessors, has no validity or respectability for the Turkish nation."

In London for a visit Thursday, Defense Secretary Robert Gates reiterated his opposition to the resolution, telling reporters that it could harm U.S.-Turkish relations at a time when U.S. forces in Iraq are relying heavily on Turkish permission to use their airspace for U.S. air cargo flights.

State Department spokesman Sean McCormack said passage of the resolution by the House would gravely harm U.S.-Turkish relations and U.S. interests in Europe and the Middle East.

"The United States recognizes the immense suffering of the Armenian people due to mass killings and forced deportations at the end of the Ottoman Empire," McCormack said in a statement. "We support a full and fair accounting of the atrocities that befell as many as 1.5 million Armenians during World War I" -- which he said the measure doesn't do.

Following Wednesday's vote, Undersecretary of State Nicholas Burns said he would call the Turkish ambassador to Washington, and that Secretary of State Condoleezza Rice would talk to Turkish leaders on Thursday.

U.S. diplomats have been quietly preparing Turkish officials for weeks for the likelihood that the resolution would pass, and asking for a muted response.

Burns said the Turks "have not been threatening anything specific" in response to the vote, and that he hopes the "disappointment can be limited to statements."

"The Turkish government leaders know there is a separation of powers in the United States, that today's action was an action by the House Foreign Affairs Committee, that this was not an action supported by President Bush and the executive branch of our government," he said.

The Bush administration has expressed concern that the vote could lead to Turkey cutting off crucial supply lines to Iraq. Defense Secretary Robert Gates said ahead of the vote that 70 percent of U.S. air cargo headed for Iraq goes through Turkey, as does about one-third of the fuel used by the U.S. military in Iraq.

"Access to airfields and to the roads and so on in Turkey would very much be put at risk if this resolution passes, and Turkey reacts as strongly as we believe they will," Gates said.

The vote also came as Turkish warplanes and helicopter gunships attacked suspected positions of Kurdish rebels near Iraq on Wednesday, a possible prelude to a cross-border operation that the Bush administration has opposed. The United States, already preoccupied with efforts to stabilize other areas of Iraq, believes that Turkish intervention in the relatively peaceful north could further destabilize the country.

The committee's vote was a triumph for well-organized Armenian-American interest groups who have lobbied Congress for decades to pass a resolution.

Following the debate and vote, which was attended by aging Armenian emigres who lived through the atrocities in what is now Turkey in their youth, the interest groups said they would fight to ensure approval by the full House.

"It is long past time for the U.S. government to acknowledge and affirm this horrible chapter of history -- the first genocide of the 20th century and a part of history that we must never forget," said Bryan Ardouny, executive director of the Armenian Assembly of America.

(Copyright 2007 by The Associated Press. All Rights Reserved.)

APTV 10-11-07 0820EDT