Andrew Mitchell's job continues to hang in the balance as the chief whip was due to meet police officers in his constituency in a bid to draw a line under a row over his alleged use of the word "pleb".
Mr Mitchell, who was accused in news reports of a foul-mouthed rant at Downing Street police officers when they would not let him cycle through the street's main gate, has apologised for not treating officers with respect but denied calling them plebs.
The senior Tory, who skipped his party's conference this week amid continuing speculation over the row, will meet representatives of his local force in his Sutton Coldfield constituency.
The West Mercia Police Federation and Labour leader Ed Miliband both called for Mr Mitchell to clarify exactly what he did say.
Ken Mackaill, chairman of the federation, said: "We want to get to the bottom of this matter, hear what Mr Mitchell has to say and hopefully move forward from here. Mr Mitchell has apologised for being discourteous to the police officers at Downing Street but has denied using the words attributed to him. We want to ask him exactly what he did say. As it currently stands, there is an implication that the officers' accounts are not accurate."
During a visit to Bristol on Thursday, Mr Miliband said: "I think the terrible thing about the Andrew Mitchell episode is we still don't know the truth. We still don't know what he said, what he said to our brave police officers, and he has got to come forward with an explanation.
"Frankly, for the Prime Minister he has got to get a grip on this situation because we've got the police officers who say that Andrew Mitchell said one thing and we've got Andrew Mitchell who has done a sort of denial of what he said.
"But Andrew Mitchell has got to come forward, and the Prime Minister has got to make him come forward, and make him say what he actually said to our police officers and nothing less than the truth about what happened in the Andrew Mitchell affair will do."
Prime Minister David Cameron has called for a line to be drawn under the affair following Mr Mitchell's earlier apologies and senior police figures have also suggested it was time to move on. Mr Cameron has insisted what happened was wrong and must not happen again but said the officers involved had not wanted to pursue the matter further.
But rank and file officers remain angry that Mr Mitchell, who was appointed chief whip in last month's reshuffle, continues to dispute the language the officers reported that he used - most controversially calling them "plebs".