Andrew Mitchell said last week that he hoped Pc Toby Rowland would give evidence on oath as part of separate libel proceedings against the Sun newspaper.
Mr Mitchell told Channel 4 News: "What I do know is that I was stitched up; I was fitted up in Downing Street by armed police officers ...
"We believe that the CCTV shows that the account of Pc Toby Rowland is at very best inaccurate."
More top news
Rescue workers are at the site Sunday morning trying to cut open mangled coaches.
Despite chilly temperatures it will be a mostly dry day, and milder than yesterday.
The Sunday Times alleges a missile malfunctioned after launch during a routine test of the UK's nuclear deterrent last year.