The Bush administration urged the Supreme Court yesterday to use a case involving federal funding of family-planning clinics to overturn Roe v. Wade, the 1973 ruling establishing a constitutional right to abortion.

In a brief, Solicitor General Kenneth W. Starr astonished abortion rights advocates, who said they had not anticipated that the administration would attempt to use the case as a vehicle for persuading the court to overrule Roe.

The case, Rust v. Sullivan, concerns federal regulations prohibiting federally funded family-planning clinics from providing information about abortion to patients and allowing them, if patients inquire, to say only that abortion is "not an appropriate method of family planning."

Critics of the regulations contend that they violate the free-speech rights of both patients and clinic employees, as well as a woman's right to make decisions about her pregnancy. The administration and other supporters say the government is not obligated to spend its money on abortion counseling.

Laurence H. Tribe, a Harvard Law School professor who is to argue the case later this year on behalf of those challenging the funding restrictions, termed the invitation to overrule Roe "gratuitous" and said the case was a "clearly irresponsible occasion" for the court to consider the vitality of Roe.

"The only event that has transpired that could account for raising it now and not {in lower courts} is the resignation of Justice {William J.} Brennan," which leaves the court with just three solid votes in support of Roe, Tribe said.

The attack on the 1973 ruling constituted one paragraph of the administration's 46-page brief and essentially repeated its arguments in an abortion case heard during the court's last term, when the justices ignored the government's invitation to tackle Roe head-on.

"We continue to believe that Roe was wrongly decided and should be overruled," the brief said.

Other cases challenging the constitutionality of newly enacted state abortion restrictions are making their way through the lower federal courts. They are expected eventually to reach the Supreme Court and determine the future of abortion rights. But the Rust case is the only abortion-related case now before the justices for review.

The filing of the brief comes the week before the Senate is to start confirmation hearings for David H. Souter, the federal appeals court judge whose views on abortion rights are unknown and have been a focus of attention since President Bush nominated him in July to replace Brennan on the high court.

The administration's argument delighted abortion opponents. The National Right to Life Committee said Bush's "firm, principled defense of unborn babies is winning him the unshakeable loyalty of hundreds of thousands of pro-life political activists."

Starr was traveling yesterday. His deputy, John G. Roberts Jr., said, "We'll let the brief speak for itself, and we'll let the court reach its own conclusions."

The brief said the court's "conclusions in Roe that there is a fundamental right to an abortion and that government has no compelling interest in protecting prenatal human life throughout pregnancy find no support in the text, structure, or history of the Constitution."

If the case is overturned, it said, the argument by those challenging the regulations that they "burden the right announced in Roe" also would fail. But the brief said the regulations would pass constitutional muster "even under Roe's strictures."

Dawn Johnsen, legal director of the National Abortion Rights Action League, said Brennan's resignation means that there is a "significant risk" that a majority of justices could decide to consider the issue.

The federal appeals court in New York upheld the regulations in the Rust case. In a separate case, the federal appeals court in Boston struck them down, as did the appeals court in Denver, in a decision yesterday.