WASHINGTON —  A U.S. diplomat nominated to be ambassador to Armenia came under intense questioning Thursday at her confirmation hearing over the U.S. policy not to label as genocide the World War I-era killings of huge numbers of Armenians.

Democratic Sen. Robert Menendez, who blocked the Bush administration's previous nominee over the issue, told The Associated Press that he had not decided whether also to block career diplomat Marie Yovanovitch.

Menendez questioned Yovanovitch in prosecutorial style during a hearing of the Senate Foreign Relations Committee about the facts surrounding the killings of Armenians by Ottoman Turks. Yovanovitch, current ambassador to the Kyrgyz Republic, explained administration policy, but would not comment whether she believed genocide had occurred.

Historians estimate that up to 1.5 million Armenians were killed, an event widely viewed by genocide scholars as the first genocide of the 20th century. Turkey denies that the deaths constituted genocide, saying the toll has been inflated, and that those killed were victims of civil war and unrest.

"It is a shame that career foreign service officers have to be brought before the committee and find difficulty in acknowledging historical facts," Menendez said. "It is a ridiculous dance that the administration is doing over the use of the term genocide."

The administration has warned that even a congressional debate on the genocide question could damage relations with Turkey, a moderate Muslim nation that is a NATO member and an important strategic ally.

In August, the White House withdrew its nomination of career diplomat Richard Hoagland after Menendez held up his confirmation through a Senate procedure.

Hoagland's predecessor, John Evans, reportedly had his tour of duty in Armenia cut short by the administration because, in a social setting, he referred to the killings as genocide.

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