The Obama administration's top spies manipulated the probe from the onset, according to John Ratcliffe

A US intelligence report on Russia's alleged interference in the 2016 presidential election, commissioned by then-President Barack Obama, was nothing but a deliberate manipulation, CIA Director John Ratcliffe has said, citing his agency's recent internal review.

Known as the 2016 Intelligence Community Assessment on Russian Election Interference (ICA), the report kickstarted the Russiagate conspiracy, prompted special counsel Robert Mueller's inquiry, and "ate up the first two years" of President Donald Trump's first term, Ratcliffe said in an interview with the New York Post published on Wednesday. The new CIA head ordered an internal review of the report in May.

Obama ordered the ICA just six weeks before leaving office. According to the CIA review of its drafting and rushed release, declassified on Wednesday, then-CIA Director John Brennan, FBI Director James Comey, and Director of National Intelligence James Clapper were unusually and "excessively involved" in the process.

"The rushed timeline to publish both classified and unclassified versions before the presidential transition raised questions about a potential political motive behind the White House tasking and timeline," the review said, calling the work on the report "chaotic," "atypical," and "markedly unconventional."

The CIA review found that Brennan effectively directed the compilation of the ICA and particularly insisted on including the later discredited Steele dossier. The dossier - a compilation of unverified rumors about Trump and his alleged links to Russia - was compiled by former British intelligence officer Christopher Steele and reportedly funded by the Hillary Clinton campaign.

"This was Obama, Comey, Clapper, and Brennan deciding, 'We're going to screw Trump,'" Ratcliffe said, commenting on his agency's findings. "It was, 'We're going to create this and put the imprimatur of an IC assessment in a way that nobody can question it.' They stamped it as Russian collusion and then classified it so nobody could see it."

"Brennan and Clapper and Comey manipulated [and] silenced all the career professionals and railroaded the process," the CIA director added.

American public opinion was further manipulated by constant media leaks and unnamed officials cited by The Washington Post, The New York Times, and other mainstream outlets.

"Before work on the assessment even began, media leaks suggesting that the IC had already reached definitive conclusions risked creating an anchoring bias," the review noted.

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The ICA, as well as the FBI's 2016 'Crossfire Hurricane' investigation and the subsequent Mueller inquiry, cast a long shadow over Trump's first term, with allegations of "Russian collusion" persisting in the media even after Mueller's report found no evidence to support them. Moscow has also repeatedly denied any election interference.