Saudi Arabia, a key U.S. regional ally, said today that it would not allow the United States to use its facilities for an attack against Iraq, even if a strike were sanctioned by the United Nations.

"We will abide by the decision of the United Nations Security Council and we will cooperate with the Security Council. But as to entering the conflict or using facilities . . . that is something else," Prince Saud Faisal, the Foreign Minister, told CNN.

"Our policy is that if the United Nations takes a decision on Chapter 7, it is obligatory on all signatories to cooperate but that is not to the extent of using facilities in the country or the military forces of the country," he added, referring to Chapter 7 of the U.N. Charter, which makes it mandatory for U.N. member countries to implement any measure immediately.

The prince's remarks were the strongest Saudi rejection of any assistance to a possible U.S. attack on Iraq.

In response to Saud's comments, Mary Matalin, an adviser to Vice President Cheney, said on CNN's "Late Edition" program that the United States had many other allies it could depend on.

Asked if the Saudi position marked a serious setback to any U.S.-led effort against Iraq, she said: "We have many friends and allies in the region and we have many friends and allies around the world. . . . We would never engage unless we were sure that we could get the job done well."

White House spokesman Ari Fleischer, speaking to reporters aboard Air Force One as President Bush flew to Springfield, Ill., on a political trip, said, "I don't talk about operational issues or basing issues," and declined to comment further.

In the past, Saud has indicated the United States could use bases in Saudi Arabia for an attack on Iraq if the strike were sanctioned by the United Nations. It was not clear what prompted the apparent shift in the Saudi position.