Instead, wearing the robe, known as an abaya, "is not mandatory but is strongly encouraged," according to an order by Gen. Tommy Franks, head of the U.S. Central Command, e-mailed to commanders in the region Saturday.
The Air Force's highest-ranking female fighter pilot is challenging the rule in court. Lt. Col. Martha McSally's lawsuit calls the policy unconstitutional and says it improperly forces American women to conform to others' religious and social customs.
McSally's lawsuit did not inspire the policy change, Central Command spokesman Col. Rick Thomas said Tuesday.
"The policy was under review before the lawsuit was filed, so the change was not a direct result of that," Thomas said.
McSally's lawsuit, filed in federal court in Washington, also challenges policies requiring servicewomen to be accompanied by a man whenever they leave their base and to ride in the back seat of a car. Women are not allowed to drive in Saudi Arabia. Thomas said those policies remain in effect.
McSally told CBS News Correspondent Lesley Stahl in an interview aired earlier this week on the program "60 Minutes" that the policy flies in the face of the U.S. Constitution.
"I can fly a single-seat aircraft in enemy territory, but I can't drive a vehicle," she said. "They turned me into a fighter pilot. This is who I am. When I see something messed up, I'm going to challenge it."
McSally will not drop her case, said John Whitehead, a lawyer with the Rutherford Institute, a religious freedom group representing her. The new policy is a step in the right direction but does not go far enough, Whitehead said.
"What it says to us is that it's not been rescinded," Whitehead said. "It's like saying, 'You're equal to us but you can't eat in the same restaurant because you're strongly encouraged to eat at one more fitting with your lower class."'
Whitehead said he has told McSally, who is now stationed at Davis-Monthan Air Force Base in Tucson, Ariz., not to comment. Officials at the Air Force base referred calls to the Rutherford Institute.
Central Command, which oversees the military in Saudi Arabia and other countries in the region, had defended the policy, put into place after the 1991 Gulf War. Central Command officials had said the requirements for servicewomen made them less likely to face harassment or attack.
McSally and other critics said the policy was ironic, since U.S. forces in Afghanistan have fought to remove the Taliban regime, which required all women to wear an even more restrictive covering called a burkha.
The change in policy "sends a strong signal that we recognize that military women in Saudi Arabia should be treated as their male compatriots are treated and be allowed to pick their civilian clothing," said Nancy Duff Campbell, co-president of the Natinal Women's Law Center. Campbell's group is not a part of the lawsuit but has lobbied members of Congress to oppose the abaya rule.
A reversal of the policy would also follow a recent warning by the chairman of the Senate Armed Services Committee who said the U.S. Air Force might need to end operations at Prince Sultan Air Base, given the restrictions on its personnel.
The United States insisted last week that all was well in the U.S.-Saudi relationship despite some signs of a strain in the wake of Sept. 11 attacks on New York and Washington.
Osama bin Laden, accused of masterminding the attacks, is of Saudi origin and has said attacks on U.S. targets are partly aimed at forcing the U.S. military out of Saudi Arabia.
The White House said Friday that President Bush wanted to keep the U.S. military presence in Saudi Arabia, despite reported grumblings from the Saudis that the United States has overstayed its welcome.
The Washington Post reported on Friday that Saudi Arabia's rulers were growing more uncomfortable with the U.S. military presence in their country and might soon ask that it end.
That report said senior Saudi rulers believed that the United States should pull out because its forces had become a political liability.
Secretary of State Colin Powell dismissed the Post report, saying there was nothing in it that warranted the attention of him or Defense Secretary Donald Rumsfeld.
Saudi Arabia depends on the United States for its defense, but has found itself walking a tightrope with increasing uneasiness among many Saudis over the presence of U.S. troops there.
If asked to leave, the United States would no longer have regular use of the Prince Sultan Air Base, where American forces have maintained a presence since the Gulf War, more than a decade ago.
"We may need to move that base," Democratic Sen. Carl Levin, chairman of the Armed Services Committee, told reporters at a breakfast last week. He said the Saudis had pressed U.S. personnel to operate at a base in a remote region and seemed to "want us out of sight."
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