A peer has resigned from the Ulster Unionist party and referred himself to the sleaze watchdog after claims he offered to act as a paid advocate for lobbyists.
Lord Laird denied breaching parliamentary rules after becoming one of three peers caught up in an undercover sting by Sunday Times reporters posing as representatives of an energy firm.
The paper said Lord Laird and Labour peers Lord Cunningham and Lord Mackenzie of Framwellgate were caught offering to ask parliamentary questions and lobby ministers in return for cash.
All three are believed to have referred themselves to the watchdog.
The Sunday Times said Laird was recorded setting out ways he could lobby for new laws on behalf of a South Korean solar power firm.
But he insisted he had suspected from the start that they were not genuine.
"In recent days I have been the subject of a scam operated by journalists masquerading as communications consultants," he said in a statement.
"This has led to allegations that I have broken the rules of the House of Lords.
"I wish to make it clear that I did not agree to act as a paid advocate in any proceedings of the House nor did I accept payment or other incentive or reward in return for providing parliamentary advice or services."
He said that because he suspected a scam, he took a journalist to the meeting as a witness.
"Shortly after the meeting, because it was so obviously a scam, we reported it to the appropriate authorities in the Lords.
"I have not broken any rules. However, I have referred the situation to the appropriate authorities and I will be making no further statement until I have received their ruling."
The latest claims emerged a day after MP Patrick Mercer quit the Tory whip after being filmed in a separate undercover operation.
He is alleged to have tabled Commons questions and offered a Westminster security pass after signing a deal with a lobbying firm that paid him £4,000 seeking the readmission of Fiji to the Commonwealth.
The lobbyists were in fact undercover reporters conducting an investigation for BBC's Panorama and the Daily Telegraph newspaper.
A Labour spokeswoman said: "The Party expects all peers to comply with the Lords Code of Conduct, which is there to bring clarity to their dealings with outside commercial interests and consultancies.
"We demand high standards of behaviour from our parliamentarians.
"Where there is genuine evidence of wrongdoing, including non-compliance with the code of conduct, the Labour Party will consider appropriate disciplinary action as and when necessary."
Mercer said he was taking legal advice but resigned the whip "to save my party embarrassment" and would step down from the Commons at the next general election.
He also referred himself to the Parliamentary Commissioner for Standards.
The MPs' code of conduct prohibits "paid advocacy" and requires the declaration of financial interests.
Tory Monmouth MP David Davies has revealed that he was among those targeted by the Panorama sting, but insisted he refused the offer of lobbying work.
Mr Mercer tabled questions to ministers in May about Fiji and also tabled a motion saying there was "no justification for Fiji's continued suspension from the Commonwealth".
The names were revealed today of some of the MPs who agreed to join an all-party parliamentary group (APPG) on Fiji at Mercer's invitation - none of whom faces any allegations of wrongdoing.
Among those named by the Sunday Telegraph were Tories Julian Brazier and Mark Field and Labour MPs Keith Vaz, Valerie Vaz and Fabian Hamilton. All defended their decision to offer support to the group.