A former colleague of the British spy linked to the Donald Trump dossier has told ITV News he is the "real James Bond".
The 35-page document on Mr Trump includes unverified allegations that Russian security officials have compromising material that could be used to blackmail the US president-elect.
Nigel West, an intelligence historian who worked alongside Chris Steele, said the former spy was the case officer for the murdered Russian defector Alexander Litvinenko.
Mr West said Mr Steele was "well respected" in the intelligence services, describing him as "short in stature, fit, wiry and intellectually very agile".
He told ITV News: "When I introduced Chris to my wife, I said 'here's the real James Bond'."
Mr West said Mr Steele is a "highly professional intelligence officer driven by evidence" who has an "analytical mind and forensic ability to get to the bottom of things very quickly".
Video report by ITV News Security Editor Rohit Kachroo
However, he said the dossier on Mr Trump was "very low value in intelligence terms", "sloppily drafted" and is in effect "briefings on gossip that's been collected from sources".
He said: "You wouldn't go to war on this document."
He added: "History will judge whether any of this report is validated. If it's validated, Chris will be confirmed as one of the great intelligence officers of the decade. If not I fear the worst."
Analysis from ITV News Washington Correspondent Robert Moore
He said Mr Steele regarded the Kremlin and Vladimir Putin's regime as a kleptocracy, saying: "This was a government that was semi-criminal that was tainted in corruption."