Anonymous allegations against Lester Crawford (search), President Bush's choice to head the Food and Drug Administration, prompted the Senate Health Committee to postpone a vote on his nomination Wednesday and request an internal FDA investigation.

The panel had scheduled a session to consider Bush's promotion of Crawford from acting to permanent head of FDA. But the committee's chairman, Sen. Mike Enzi, R-Wyo., and the ranking Democrat, Sen. Edward Kennedy (search) of Massachusetts, announced, "We are postponing the scheduled vote on Dr. Crawford's nomination to provide more time to address issues that have been raised on both sides of the aisle."

Later, in response to questions, committee spokesman Craig Orfield added that Enzi had requested that the FDA's Office of Internal Affairs "open an investigation into allegations concerning Dr. Crawford made by an anonymous FDA employee." Orfield said an FDA employee anonymously delivered the allegations to the committee and that Enzi had forwarded them to the White House.

Orfield declined to provide any details of the allegations. Enzi hopes "the investigation will be conducted expeditiously," Orfield said.

Asked about the development, White House press secretary Scott McClellan said, "The president believes Dr. Crawford is a highly qualified nominee, and we hope the committee will move forward quickly and send his nomination to the floor."

The FDA (search) had no immediate comment.

A committee aide said the panel was unable on its own to check the validity of the allegations and did not know the identity of the purported FDA employee making them.

"This was an eleventh-hour surprise to us. We were ready to vote," said the aide, who spoke on condition of anonymity because he was going beyond the official statement.

The aide added that the White House had told the panel it believed the allegations would not be substantiated, but the aide was not able to say on what basis the White House said that.

The White House normally conducts FBI background checks on presidential nominees. It was not clear if any background check on Crawford dealt with the allegations.

A week ago, two Democratic senators, Patty Murray of Washington and Hillary Rodham Clinton of New York, said they would block Crawford's nomination because they were unsatisfied with his explanation of why the "morning-after pill" has not been approved for use without a prescription. Under Senate tradition, one senator can block Senate action on a nomination.

Barr Labs submitted its application to sell the morning-after pill over the counter in April 2003. Federal health advisers voted 24-3 in December 2003 in favor of allowing over-the-counter sales of the pill, also known as Plan B.

In a confirmation hearing four weeks ago, Democrats repeatedly asked Crawford why the FDA had not yet reached a decision. Crawford said that the company's application was unique and complex and that he was awaiting further information.