Michael Martin confirmed on Wednesday night that he would stand down as an MP when he resigns as Speaker next month, ending a day of hectic speculation in Westminster over whether he would seek to cling on to his seat in defiance of convention.

Even after his dramatic resignation on Tuesday, Mr Martin was still seeking precedents to justify staying on as an MP. Mr Martin’s friends reacted angrily to news that he would quit, claiming he was the victim of poor advice from the Speaker’s office.