The Conservative Party has suspended the whip from former foreign secretary Malcolm Rifkind, and a party disciplinary committee will investigate cash-for-access allegations resulting from an undercover sting operation.
Mr Rifkind, who chairs the parliamentary committee which oversees Britain’s intelligence agencies, was one of two senior parliamentarians secretly filmed by reporters posing as representatives of a fictitious Hong Kong-based firm seeking to hire senior British politicians to join its advisory board.
The veteran MP is said to have claimed that he could arrange "useful access" to every British ambassador in the world because of his status, while Labour's former foreign secretary Jack Straw boasted of operating "under the radar" to use his influence to change European Union rules on behalf of a commodity firm which paid him £60,000 (€81,370) a year.
Following a meeting between Mr Rifkind and Tory Chief Whip Michael Gove this morning, a Conservative source said: "The Conservative Party has suspended the whip from Sir Malcolm Rifkind — effective immediately.
“A disciplinary committee of the party will be convened to investigate his case.”
Mr Straw said he was "mortified" to have fallen for the undercover operation by the Daily Telegraph and Channel 4's Dispatches and agreed to suspend himself from the Parliamentary Labour Party, while Conservative Mr Rifkind said he was "irritated and angry" over the sting and insisted he had "nothing to be embarrassed about".
Both men have strongly denied any wrongdoing and have referred themselves to the Parliamentary Commissioner for Standards.
In a letter to David Cameron, Mr Miliband urged the British prime minister to show “action and leadership” in following his lead in banning his MPs from holding directorships and consultancies while they are serving at Westminster.
Labour MPs and prospective parliamentary candidates have already been warned that the party’s rulebook will be changed to stop them holding such posts after the May general election — a commitment Mr Miliband confirmed will be in the Labour manifesto.
And the Labour leader also revealed he is consulting on legislation to put the ban into law for all MPs and to impose a cap on outside income similar to that in place for members of Congress in the US, who may earn no more than the equivalent of 15 per cent of a minister of state’s salary on top of their pay as lawmakers.
Party sources stressed that no figure has been set on the proposed cap, but the US example suggests that a level of around £5,000-£15,000 a year may be under consideration.
Mr Miliband told the prime minister: “The British people need to know that when they vote they are electing someone who will represent them directly, and not be swayed by what they may owe to the interests of others.
“There have been too many scandals about conflicts of interest in recent years. It is time to draw a line under this and ensure these current allegations are the last.”