Andrew Mitchell MP and the policeman who accused him of calling him a "pleb" are set for a showdown in court after both insisted they are telling the truth.
Mr Mitchell claimed CCTV footage of the 'plebgate' incident supports his claim he had been "stitched up" by police.
Speaking at a news conference after it was announced that one officer, PC Keith Wallis, had been charged with misconduct in public office over the affair, Mr Mitchell said: "I have told the truth … the police did not."
Mr Mitchell presented CCTV footage of the incident outside Downing Street and claimed it proved he could not have said the words alleged by officers during the timeframe shown.
He had been accused of using the words "****ing plebs" and "you should know your ****ing place".
Mr Mitchell said PC Toby Rowland, the officer at the gate who alleged he was subjected to those insults, was not telling the truth and said he would like to swear that under oath.
But PC Rowland later released a statement saying he stands by his account.
"This has now been thoroughly investigated and the CPS has confirmed there is insufficient evidence to take any criminal proceedings against me," the statement said.
"In addition, neither am I subject to any disciplinary proceedings. I confirm that I am prepared to give evidence under oath if required."
It comes after it was revealed that PC Rowland would face no criminal charges or misconduct hearing.
Mr Mitchell said: "Police Constable Toby Rowland, who was responsible for writing these toxic phrases into his notebook, was not telling the truth."
He also said the video disproved PC Rowland's statement that "several members of the public" outside the gates had witnessed the exchange and were shocked by what they heard.
Mr Mitchell claimed that Scotland Yard's investigation into plebgate cast "grave doubt on the ability of the police to investigate wrongdoing in their own ranks".
He said that the inquiry had "meandered on for more than a year", and caused "huge and unnecessary" public expense.
The decision not to focus on PC Rowland let investigators centre on less important issues, he claimed.
"This has allowed the inquiry to focus on the secondary issues rather than the incendiary fact that armed police officers...have stitched up one of those they are supposed to protect," he said.
He said he was taking libel action against the Sun newspaper and that he expected PC Rowland would be called to give evidence in court as part of that case.
Mr Mitchell claimed his reputation had been destroyed by the allegations, that his mother-in-law was pursued in Swansea and that he had been spat at in the street. He also said the episode had been used to "toxify" the Conservative Party.
Meanwhile, Independent Police Complaints Commission deputy chairman Deborah Glass issued a statement after the watchdog said PC Wallis and four other police officers, all from the Metropolitan Police Diplomatic Protection Group, would face gross misconduct disciplinary proceedings.
"Those officers who may be responsible for turning a largely inaudible altercation lasting less than a minute into a national scandal plainly have a case to answer for gross misconduct," she said.
All five of the officers facing disciplinary proceedings could lose their jobs.