Dec. 6 (Bloomberg) -- CIA agents would be banned from simulating drowning, or waterboarding, in questioning suspected terrorists under legislation agreed to by House and Senate negotiators, lawmakers said.

The legislation would require all spy agencies to follow the Army Field Manual's interrogation standards, which ban waterboarding and other harsh techniques, members of the Senate Intelligence Committee said in separate statements.

Waterboarding became politically controversial following news reports that the CIA had used the technique three times to interrogate suspected al-Qaeda operatives after the Sept. 11 attacks. It hasn't been used since 2003, according to reports.

``The national debate over torture will end if this amendment to place the CIA under the Army Field Manual becomes law,'' California Senator Dianne Feinstein, a sponsor of the provision, said in a statement. ``All U.S. government interrogations, military and civilian, would be conducted under the same rules.''

If passed by Congress, the ban might prompt a veto by President George W. Bush, who has argued that intelligence agents need flexibility in questioning suspected terrorists. The Bush administration has denied that agents ever tortured prisoners to extract information.

Presidential spokeswoman Dana Perino said today such a provision ``is something the president has opposed in the past and that we would have a veto threat on.''

Field Manual

The provision require the CIA and other civilian agencies to comply with the ban on waterboarding and seven other harsh interrogation techniques by military personnel that are contained in the Army Field Manual.

The proposed ban is ``a killer amendment'' that ``would essentially put the CIA out of business,'' said Missouri Senator Christopher Bond, vice chairman of the Senate Intelligence Committee.

Besides Feinstein, the provision was also sponsored by Democrats Russell Feingold of Wisconsin and Sheldon Whitehouse of Rhode Island and Nebraska Republican Chuck Hagel.

Congress, under Republican control last year, passed legislation to limit harsh interrogation of prisoners without specifying what techniques should be prohibited. Instead, it gave the president discretion to determine what techniques would violate international agreements banning outrages against personal dignity and other degrading treatment.

Geneva Convention

A group of Republicans led by Arizona Senator John McCain, a former Navy pilot who was taken prisoner in North Vietnam during the Vietnam War, forced Bush to accept a provision that interrogations wouldn't violate the 1949 Geneva Conventions barring ``degrading treatment.''

In an October interview with Charlie Rose on his public television show, CIA Director Michael Hayden said the agency had changed its interrogation methods, such as subjecting prisoners to sensory deprivation.

``Interrogation can and should be carried out using techniques that have been used with success by military and law enforcement interrogators for decades,'' Senator Jay Rockefeller, the West Virginia Democrat who heads the Senate intelligence panel, said in a statement. ``A separate program shrouded in secrecy'' only ``plays into the hands or our enemies,'' he said.

To contact the reporter on this story: James Rowley in Washington at jarowley@bloomberg.net.

Last Updated: December 6, 2007 18:24 EST