David Cameron was today accused of presiding over a “cover-up” over Conservative Chief Whip Andrew Mitchell's altercation with a Downing Street police officer.
After No 10 last night ruled out an official inquiry into the encounter, shadow home secretary Yvette Cooper said the Prime Minister appeared determined to prevent the truth coming out.
Pressure on Mr Mitchell intensified after The Daily Telegraph published the full 442-word police log of the incident, which showed he called officers "plebs" and swore at them repeatedly.
While he has apologised for showing a lack of respect to the police, Mr Mitchell insisted he did not use the words attributed to him - prompting angry complaints from the Police Federation that he was effectively accusing the officers involved of lying.
The Cabinet Secretary Sir Jeremy Heywood last night attempted to draw a line under the matter, arguing that there was no purpose in holding an inquiry as the officer concerned had accepted Mr Mitchell's apology and did not wish to pursue the matter.
However Ms Cooper said that it was essential to establish who was telling the truth.
"It now looks like there is a cover-up going on and really I think both Andrew Mitchell and the prime minister need to tell us exactly what is happening," she told ITV's Daybreak.
"You read these reports and you have got a cabinet minister not just swearing at the police but also sneering at them, calling them plebs, saying they should know their place.
"I don't think the Prime Minister can just dismiss this and try and sweep this under the carpet.
"I think people will want to know the truth across the country and at the moment, so far, the Government just seem to be trying to clamp down and trying to prevent that coming out."
Home Office Minister James Brokenshire insisted that it was possible that both Mr Mitchell and the officer genuinely had different recollections of what happened.
"I have got no reason to doubt the recollections of either Andrew Mitchell or the police officer concerned," he told Sky News.
"It may well be that they can both honestly believe that their recollection of those events is as has been recorded."
Mr Mitchell also finally received the backing of the Tories' Liberal Democrat coalition partners.
After Business Secretary Vince Cable yesterday revelled in Mr Mitchell's discomfort during his speech to the Lib Dem party conference in Brighton, Treasury Chief Secretary Danny Alexander said it was now time to move on.
"Andrew Mitchell has apologised for what he did," he said. "I gather he has apologised directly to the police. I think we should draw a line under the matter now."
According to the Telegraph, the police log describes Mr Mitchell speaking to a female officer on Wednesday evening and "demanding exit through the main vehicle gate into Whitehall".
He was told that it was "policy" for cyclists to use the pedestrian gate.
"Mr Mitchell refused, stating he was the Chief Whip and he always used the main gates," the report goes on.
"I explained to Mr Mitchell that the policy was to use the side pedestrian gates and that I was happy to open those for him, but that no officer present would be opening the main gates as this was the policy we were directed to follow.
"Mr Mitchell refused. Repeatedly reiterating he was the Chief Whip... After several refusals Mr Mitchell got off his bike and walked to the pedestrian gate with me after I again offered to open that for him.
"There were several members of public present as is the norm opposite the pedestrian gate and as we neared it, Mr Mitchell said: 'Best you learn your f****** place... you don't run this f****** Government... You're ******* plebs.'
"The members of public looked visibly shocked and I was somewhat taken aback by the language used and the view expressed by a senior Government official. I cannot say if this statement was aimed at me individually, or the officers present or the police service as a whole."
The log states that the officer warned Mr Mitchell that he could be arrested for swearing.
"I warned Mr Mitchell that he should not swear, and if he continued to do so I would have no option but to arrest him under the Public Order Act, saying 'Please don't swear at me, sir. If you continue to I will have no option but to arrest you under the Public Order Act'," it states.
"Mr Mitchell was then silent and left saying 'You haven't heard the last of this' as he cycled off."