Former U.S. National Security Adviser Condoleezza Rice gave the go-ahead to the CIA for an interrogation program that included the method known as waterboarding in 2002, and Vice President Dick Cheney affirmed White House support a year later, a Senate Intelligence Committee report said on Wednesday.

The report, compiled with Justice Department assistance, comes as pressure is building to investigate and prosecute high-level Bush administration officials who authorized the harsh interrogations of terrorism suspects.

Waterboarding, a form of simulated drowning, has been widely condemned as illegal torture.

Following is a timeline describing the development of the interrogation policy, according to the report.

* April 2002: The CIA begins discussing with senior Bush administration officials plans to interrogate recently captured al Qaeda suspect Abu Zubaydah, who the CIA believed was withholding information about pending attacks.

* Mid-May 2002: CIA attorneys meet Rice, Attorney General John Ashcroft and White House Counsel Alberto Gonzales to discuss using alternative interrogation methods. The report said, At this meeting, the CIA proposed particular alternative interrogation methods, including waterboarding.

* July 17, 2002: CIA Director George Tenet meets Rice, who advised that the CIA could proceed with its proposed interrogation of Abu Zubaydah, subject to a favorable legal opinion from the Justice Department.

* August 1, 2002: The Justice Department issues two formal opinions and a memo authorizing waterboarding and other proposed harsh interrogation techniques. The report said, The classified opinion concluded that none of the proposed interrogation techniques, used individually or in combination, would violate the criminal prohibition against torture.

* 2002-2003: After receiving legal approval, the CIA went forward with the interrogation of Abu Zubaydah and with the interrogation of other high-value al Qaeda detainees. The report said, Waterboarding was used on three detainees: Abu Zubaydah, Abd al-Rahim al-Nashiri, and (accused September 11 plotter) Khalid Sheik Mohammed.

* Autumn 2002: The CIA briefs the Senate Intelligence Committee chairman and vice chairman on the Zubaydah interrogation. In early 2003, the CIA briefs the new committee chairman and key staff.

* April 2003: Tenet requests an official re-affirmation of the interrogation program.

* July 2003: Tenet and CIA lawyer meet Cheney, Rice, Ashcroft, Gonzales and others to describe the interrogation techniques, including waterboarding. The report said, At the conclusion of that meeting, the Principals reaffirmed that the CIA program was lawful and reflected administration policy.

* September 16, 2003: The CIA briefs Secretary of State Colin Powell and Defense Secretary Donald Rumsfeld on the agency's interrogation techniques, at Rice's request.

* June 2004: A CIA inspector general review of the interrogation program is given to the heads of the Senate Intelligence Committee. The CIA seeks an updated Justice Department legal opinion and analysis of whether the interrogation program meets international anti-torture standards.

* The Justice Department withdraws one of the August 1, 2002 opinions approving the interrogation program.

* July 22, 2004: Ashcroft tells the CIA that the techniques authorized in August 2002, other than waterboarding, would not violate U.S. law, treaty obligations or the Constitution.

The CIA nonetheless chose not to use waterboarding in 2004. Waterboarding was not subsequently used on any detainee, and was removed from CIA's authorized list of techniques sometime after 2005, the report said.

* May 2005: Justice Department legal opinions again approve harsh interrogations.

* February 2008: CIA Director Michael Hayden discloses the use of waterboarding. Director of National Intelligence Michael McConnell says waterboarding is no longer being used by CIA.

* January 22, 2009: New President Barack Obama bans waterboarding and other harsh techniques, and declares invalid all Bush-era Justice Department opinions on interrogations.