Eric Joyce has resigned from the Labour Party after admitting assault in a House of Commons bar brawl.
Joyce was suspended from the party following the fracas in the Strangers' Bar in Westminster on 22 February. During the incident, he launched a drunken attack on Conservative MPs.
He pleaded guilty to four counts of assault on 9 March and was handed a £3,000 fine, along with a three-month ban from London pubs.
Joyce, who gave a refreshingly frank and honest apology outside the court following his sentencing, also took the opportunity to address the House, where he announced his resignation from Labour.
"Members will be aware of the events at Strangers' Bar, during which the standards of my conduct fell egregiously below what is required not just of a member of this House, but of anyone anywhere," he said.
He took the opportunity to apologise "without reservation" to the victims of his violent outburst, including Conservatives Stuart Andrew, Luke Mackenzie and Ben Maney, as well as Labour whip Phil Wilson.
"Clearly, I have a number of personal issues to attend to and you can be assured that this will take place," he added.
"In the meantime, a number of short-term restraints have been placed upon me by the court. I would also like to inform the house that I have tended my resignation as a member of the Labour Party."
Joyce, who has vowed to confront his issues with alcohol and a "tendency toward being aggressive physically", will step down from his position as MP at the next general election, but has vowed to continue his duties until then.
He has been MP for Falkirk since 2000 and served in the Army Education Corps before embarking on a career in politics.