A Labour MP has demanded an inquiry following claims of a confrontation with a backbench colleague who was strongly against the Terrorism Bill.
Mr Marshall-Andrews has been fiercely against the Terrorism Bill
Jim Dowd, MP for Lewisham West, said he has filed a complaint against Labour's Medway MP Bob Marshall-Andrews, under the Parliamentary code of conduct.
Mr Dowd admitted he "seized the lapel" of Mr Marshall-Andrews, a barrister, but denied any blows were exchanged.
Mr Marshall-Andrews told BBC Radio Kent he knew "nothing about this at all".
He insisted nothing untoward happened.
Mr Dowd claimed a clash happened at about 2130 GMT in the Members' Lobby of the Commons.
He went on: "Mr Marshall-Andrews was holding court with three Tory MPs. One of my other colleagues had words with him - I was standing some distance away - and that seemed quite heated.
"I went over to speak to my colleague and Mr Marshall-Andrews gratuitously issued the most offensive insult directed to me. It was fairly vile and offensive.
"I demanded that he apologise immediately, but he did not."
Mr Dowd has asked Chief Whip Hilary Armstrong to investigate.
Pressed on whether the confrontation became physical, Mr Dowd, said: "I did move towards him. I think the traditional expression is I seized his lapel. I was extremely angry."
But he insisted: "There were no blows exchanged."