WASHINGTON -- Senate Republicans yesterday rejected a full inquiry of the domestic spying program that was secretly authorized by President Bush, but they said they would push to impose new limits on the administration's ability to eavesdrop on Americans' phone calls and e-mail messages without a warrant.
In a party-line vote, the Republicans who control the Senate Select Committee on Intelligence also created a subcommittee of seven senators who will have access to more details of the wiretapping program in the future.
Republican leaders said they would act soon to limit unauthorized government surveillance of a terrorism suspect to an initial period of 45 days.
Then, the administration would have to get clearance from a special national security court or certify to the new subcommittee that seeking a court warrant would jeopardize national security.
Democrats angrily accused Republicans of bowing to pressure from the Bush administration, which insists that any investigation of the program could jeopardize national security.
''The committee is, to put it bluntly, is basically under the control of the White House," said Senator John D. Rockefeller IV, a West Virginia Democrat and the intelligence committee's vice chairman. ''You can't legislate properly unless you know what's going on."
Rockefeller said the Republicans' bill leaves Congress to ''legislate in darkness and ignorance."
He said that lawmakers still do not know how many telephone calls and e-mail messages that the National Security Agency is monitoring, or whether it has thwarted any possible terrorist attacks.
But Republicans say the new subcommittee and the bill that would set a 45-day deadline on secret surveillance add up to significant new oversight of a program they assert is a vital tool to combat terrorism.
''It provides for a case-by-case examination and oversight by the United States Congress," said Senator Mike DeWine, an Ohio Republican who is helping draft the new bill. ''It will be very consistent with what our constitutional obligations are."
The discussions occurred amid rising concerns from both parties over the details of the top-secret program. The Senate Judiciary Committee chairman, Arlen Specter, Republican of Pennsylvania, said yesterday that he may try to cut off funding for the program unless the administration answers more questions.
''We're having quite a time in getting responses . . . as to what has happened with the electronic surveillance program," Specter said before the Senate Appropriations Committee. ''I want to put the administration on notice and this committee on notice that I may be looking for an amendment to limit funding as to the electronic surveillance program -- which is the power of the purse -- if we can't get an answer in any other way."
Shortly after the Sept. 11, 2001, terrorist attacks, Bush bypassed Congress and the courts to secretly authorize the NSA to listen in on Americans' international phone calls and e-mail messages. Under a 1978 surveillance law, the government must obtain court permission when it wants to spy on US citizens in the interest of national security.
The program came to light in December in an article that was published by The New York Times.
Specter has held two hearings on the program's legality, and has separately proposed that a special national security court be asked to determine whether it might violate the US Constitution.
Yesterday's Intelligence Committee bill has the support of the chairman, Pat Roberts, Republican of Kansas, and the Senate majority leader, Bill Frist, a Tennessee Republican. DeWine said the White House supports the bill in principle but is withholding judgment until the final draft.
Critics contend that the bill would allow the Bush administration to skirt the 45-day deadline by declaring that national security is at stake whenever a case is questioned. DeWine's bill would not give the committee the authority to intervene, even in cases in which wiretapping appears to be unjustified.
''The White House could just decide not to tell them everything, and there's no sanction," said Bruce Fein, a former Reagan administration lawyer who said he believes that the NSA program is illegal. ''And the president can still claim that he has inherent power to conduct surveillance."
But DeWine said the new subcommittee will give four Republicans and three Democrats access to new details of the program. If lawmakers think the president is abusing his authority, they can recommend steps to curb it, the bill's supporters said.
''We are reasserting congressional responsibility and oversight," said Senator Olympia J. Snowe, a Maine Republican who has voiced concerns about the legality of the program. ''This program should not continue in an unfettered fashion, without significant congressional and judicial checks on the process."
Still, the bill appears deferential to the White House, said Douglas Kmiec, a Reagan administration lawyer who agrees with Bush that the program is legal.
''It's extremely generous to the president," said Kmiec, a Pepperdine University law professor. ''It is not significantly different from the status quo. And I think the president would be quite delighted by that."