Lord Laird has resigned the Ulster Unionist whip pending an inquiry into allegations he broke parliamentary rules.
The peer is alleged to have offered to carry out parliamentary work for cash after being caught in two separate stings by undercover journalists posing as lobbyists.
He denies any wrongdoing and has referred the case to a sleaze watchdog.
In a statement, party leader Mike Nesbitt said: "Having reviewed the video footage on the Daily Telegraph website, and other media reporting of Lord Laird's engagement with alleged lobbyists, I telephoned his home this morning and as a result he has relinquished the Party Whip, pending the outcome of the review of his behaviour that he has already requested of the relevant authorities at Westminster."
Three members of Britain’s upper house of parliament are today accused of offering to use their influence for personal gain in a widening scandal over the improper influence of paying lobbyists over legislators.
In addition to Lord Laird, the House of Lords peers caught up in an undercover reporting “sting” from the Sunday Times newspaper are John Cunningham and Brian Mackenzie of the main opposition Labour Party.
All three denied breaking the chamber’s rules.
The trio were covertly filmed offering to ask parliamentary questions, lobby ministers and host events in prestigious House of Lords premises in exchange for payment by what they were told were lobbyists acting for companies.
The scandal will renew pressure on Prime Minister David Cameron to introduce a statutory register of lobbyists, as promised in 2010 in the coalition agreement between his Conservatives and their junior partners, the Liberal Democrats.
Mr Cameron warned more than three years ago that lobbying was “the next big scandal waiting to happen” but critics, including some Liberal Democrats, accuse him of dragging his feet.
“The coalition agreement promised action, and cross-party support was offered. However, scandals around ‘cash for access’ continue to be present at the heart of this government,” said Labour legislator Jon Trickett, speaking for the party.
Sunday Times reporters approached Mr Cunningham, a former minister under then Prime Minister Tony Blair in the 1990s, pretending to represent a South Korean solar energy company.
“Are you suggesting £10,000 a month? Make that . . . £12,000 a month. I think we could do a deal on that,” he was quoted as saying by the newspaper during a discussion about his fees for what was described as consultancy work.
Mr Cunningham later sent a statement to the Sunday Times saying he had referred to “a fanciful £12,000 a month” to test his suspicion that he was talking to undercover journalists.
“I deny any agreement to operate in breach of the House of Lords code of conduct and, in fact, recall that I made it clear that I would only operate within the rules,” Mr Cunningham said in the statement sent to the Sunday Times.
Lord Laird also issued a statement denying he had broken the rules, and Mr Mackenzie denied wrongdoing in a BBC radio interview.