The House of Lords standards commissioner has begun investigating the three peers caught up in a lobbying scandal, it was announced today.
Leader of the House Lord Hill of Oareford described the allegations as "very serious and distressing".
In a short statement he said ex-cabinet minister Lord Cunningham and Lord Mackenzie of Framwellgate, who have both been suspended by Labour, and Lord Laird, who has resigned from the Ulster Unionists, would all be investigated.
The three, who deny any wrongdoing and referred themselves to the standards watchdog, were caught in an undercover sting by Sunday Times reporters posing as lobbyists working for a fake energy firm.
Lord Hill told peers: "The sub-committee on Lords conduct agreed to a request earlier today from the House of Lords commissioner for standards, Mr Paul Kernaghan, that he proceed to investigate the three members of this House against whom allegations have been made.
"Independent external investigation of these allegations is therefore in hand."
He added: "For the last three years we have had in place a clear code of conduct to regulate our behaviour as members of this House and we have also had an independent commissioner for standards whose task it is to investigate whether there has been a breach of that code.
"I'm pleased that the necessary preliminary steps to secure a proper investigation have already been taken and from this point it is now over to the commissioner, who will make his report in each case to the sub-committee on Lords conduct.
"The allegations made at the weekend are very serious and distressing to us all. I know I speak for all the parties when I say they do not reflect the House we know and the members who work here from a sense of public service, a desire to hold the Government to account and to revise legislation."