Andrew Bridgen has reported a fellow MP to parliamentary authorities for allegedly slapping him on the back of the head and calling him a “bastard”.

Mr Bridgen, who joined the Reclaim Party after being kicked out of the Conservatives, demanded that Tory Crispin Blunt apologises for the “chop” in Parliament on Monday.

Parliamentary officials confirmed they were aware of the incident in the atrium of Portcullis House and said the Commons authorities and the whips’ office were dealing with it.

I’m asking for an apology, it’s just unbelievable behaviour

Mr Blunt, a former minister who represents Reigate, has not responded to requests for comment.

Mr Bridgen, the MP for North West Leicestershire, who said he was not injured in the incident, claimed there was a “number of witnesses” who saw the incident and they had spoken to Parliament’s authorities after he reported it to security.

He told the PA news agency: “I was sitting at one of the round tables in Portcullis House and he went by the back of me and hit me on the back of the head with his hand and said, ‘You’re a bastard’ and then legged it off.

“I was just completely shocked. That’s not the behaviour you would expect from a Member of Parliament.

“I’m asking for an apology, it’s just unbelievable behaviour.”

Mr Bridgen believed that the incident was “completely unprovoked”, apart from him having questioned to a newspaper why he had the whip removed by the Tories but Mr Blunt has not for past comments about Hamas.

A parliamentary spokesman said: “The Behaviour Code makes clear the standards of behaviour expected of everyone in Parliament – whether MPs, staff, Members’ staff, members of the House of Lords, press, contractors or visitors.

“There is zero tolerance for abuse or harassment.”