Johnny Mercer has alleged that the deputy chief whip attempted to "blackmail" him into backing Theresa May's Brexit deal.
The Conservative MP claimed his friends in the Army were asked by whips for "dirt", but said he was then told they just wanted to "kick the tyres" and check on his military background.
But Mr Mercer, who has toured Afghanistan in service, said he believed the deputy chief whip was looking for material to blackmail him during an appearance on the BBC show, Have I Got News For You.
"The deputy chief whip has decided to go and ask friends of mine that I served with in the military whether or not things in my book were correct," he said.
"When I confronted him about it, he claimed that was his job to 'kick the tyres'.
"When I spoke to my friend, he hadn't done anything like that at all - he'd tried to get some dirt and blackmail me to vote for the Prime Minister's deal in January."
Guest host of the show, David Tennant, asked the MP: "So that's why they did it - to try and force your vote?".
Mr Mercer replied: "Yeah. Nice place, politics. Why did I sign up?".
talkRADIO has approached deputy chief whip Christopher Pincher for comment.