WASHINGTON - Senior Bush administration officials signed off on the CIAs use of waterboarding and other harsh interrogation measures in July 2002, after a series of secret meetings that apparently excluded the State and Defence Departments, according to information released Wednesday by the Senate Intelligence Committee. The Senate report indicates that then-National Security Adviser Condoleezza Rice, then-Attorney General John Ashcroft and other officials gave the CIAs interrogation plan political backing even before the methods the agency was about to employ had been approved by the Justice Department. The document also reveals the existence of a series of Justice Department memos written in 2006 and 2007 that in some cases undermined congressional efforts to rein in the CIAs interrogation authorities memos that have not been publicly acknowledged and were excluded from the batch released last week by the Obama administration. The document represents the most complete chronology to date of the Bush administrations embrace of waterboarding and other interrogation techniques. In listing the senior Bush administration officials intimately involved in the early deliberations on CIA interrogations, the report underscores how any effort to hold architects of the programme accountable is likely to extend into the highest reaches of the govt. It also raises questions about whether the Bush administration sought to keep details of the CIA program away from top officials - particularly then-Secretary of State Colin Powell - who were perceived as potential opponents of the use of such methods. The Senate report is a summary of documents that the committee obtained from the CIA. Its declassification is likely to add to the momentum for an independent inquiry on interrogations. Senator John Rockefeller, the former Democratic chairman of the Senate Intelligence Committee who had pushed for the panels report to be declassified, said the document demonstrates how deeply involved the Bush White House was in designing the CIAs interrogation programme. The records of the CIA demonstrate that the lawyers at the Office of Legal Counsel did not operate in a vacuum, Rockefeller said in a statement, referring to the Justice Department office that issued many of the key legal opinions endorsing the CIAs use of harsh interrogation methods. The then-vice president and the national security adviser are at the centre of these discussions. The report identifies Dr Rice as the official who advised that the CIA could proceed with its interrogation of Abu Zubaydah, the first high-level Al Qaeda operative captured by the agency and the first to be subjected to waterboarding and other harsh methods. That message was sent July 17, 2002, according to the document, pinpointing for the first time the date that the Bush administration formally backed the CIAs aggressive interrogation plan. The report notes that Rices endorsement, conveyed to then-CIA Director George Tenet, was subject to a determination of legality by the OLC. That came one week later when CIA was informed that Ashcroft had concluded the proposed techniques, including waterboarding, were lawful. One former Bush administration official familiar with the interrogation discussions said in an interview that the CIA programme was presented as the only way to prevent further attacks following Sept 11. It wasnt until September 2003 that the CIA briefed Powell and then-Defence Secretary Donald Rumsfeld on the interrogation programme, according to the Senate report.