Senate Republicans planned to push ahead with legislation regulating the treatment and interrogation of terrorism suspects in U.S. custody, despite a White House veto threat.

The Bush administration, led by Vice President Dick Cheney, is working to kill amendments that GOP Sens. John McCain (search) of Arizona and Lindsey Graham (search) of South Carolina want to tack onto a bill setting Defense Department policy for next year.

McCain, a former prisoner of war in Vietnam, and Graham, a former military lawyer, planned to introduce their amendments this week, said Senate aides who spoke on condition of anonymity because they were not authorized to let their names be used. Senate Armed Services Committee Chairman John Warner, R-Va., has been working with McCain and Graham on the legislation.

The aides said the measures have not been toned down even though White House lobbying against them intensified late last week.

Cheney met with the three Republican lawmakers just off the Senate floor for about 30 minutes Thursday evening. That followed an administration statement that President Bush's advisers would recommend a veto of the overall bill if amendments were added that "interfere with the protection of Americans from terrorism by diverting resources from the war to answer unnecessary or duplicative inquiry or by restricting the president's ability to conduct the war effectively."

Senate aides estimate that nearly a dozen Republicans could be on board — which would be more than enough for the amendments to pass. Democrats, who long have criticized the administration on detainee treatment, are roundly supportive.

Talk of legislation regulating U.S. treatment of terror suspects has percolated on Capitol Hill since last year when the Abu Ghraib (search) prison abuse scandal in Iraq surfaced.

But the effort by the leading Republicans to standardize treatment of terror suspects has gained steam over the past few months. Criticism by human-rights groups and lawmakers over the military's detainee camp in Guantanamo Bay (search), Cuba, reached a fever pitch this spring amid fresh allegations of abuse and torture there.

McCain's package of amendments would make interrogation techniques outlined in the Army field manual — and any future versions of it — the standard for treatment of all detainees in the Defense Department's custody. It also would expressly prohibit the cruel, inhumane and degrading treatment of prisoners in U.S. custody no matter where they are held.

The United States also would have to register all detainees in Defense Department facilities with the Red Cross to ensure all are accounted for. The Pentagon has acknowledged holding up to 100 so-called "ghost detainees," who are not listed in regular prison logs.

McCain supports a pair of amendments Democrats are likely to sponsor prohibiting the United States from exporting terror suspects to countries that are known to torture prisoners, and requiring the United States to register with the Red Cross detainees who are held outside of Defense Department facilities.

Graham's amendment would make law the procedures the Bush administration has put in place for prosecuting cases of detainees at Guantanamo Bay.

However, it also would allow detainees to have a military lawyer — not just a military representative — available when appearing before annual review boards. Like parole boards, these panels determine whether the detainee still poses a threat to the United States and, if so, should remain in custody.

"Without congressional authority, we run a real risk a federal court will either take over or impede our efforts" at Guantanamo, Graham said in a statement. "We need to have a congressional buy-in into this matter."

The amendments have the support of 14 retired military officers, including former Rep. Douglas "Pete" Peterson, a Vietnam veteran and prisoner of war. "The United States should have one standard for interrogating enemy prisoners that is effective, lawful, and humane," they said in a statement.

Democrats — led by Sen. Carl Levin of Michigan, the top Democrat on the Senate Armed Services Committee — plan to introduce an amendment that would set up an independent commission to review detention and interrogation practices at Guantanamo Bay and elsewhere.