The four peers at the centre of the "cash-for-amendments" allegations could face emergency sanctions if the claims against them are proven, the Leader of the House of Lords has said.
Baroness Royall of Blaisdon also indicated that new rules governing outside interests would be introduced - backed up by the threat of expulsion from the Lords in the worst cases.
Her comments came as Tory leader David Cameron also vowed to introduce tougher penalties, including stripping members of the House of Lords of their peerages.
Currently, there are no sanctions that can be made against peers except to bring their behaviour to the attention of the House of Lords in a debate.
But Lady Royall warned that the four Labour peers accused of offering to amend legislation in return for payments would not escape punishment if they were found guilty.
In an article for The Guardian, she said the rules would be changed so that peers cannot "earn a living (that) warps their work as parliamentarians".
"If there are abuses, they must be rooted out," she said.
"So I will be recommending that we should be able to take a range of actions as necessary, including being able to suspend peers immediately while an investigation is being carried out, longer periods of suspension if cases are proven, and even consider the option not of removing peerages - not in the gift of the House - but of even longer and perhaps permanent exclusions in extreme cases.
"If the current allegations are proven, we may need as well to consider emergency sanctions if warranted."
Lord Truscott, Lord Moonie, Lord Taylor of Blackburn and Lord Snape are accused of entering into negotiations, involving fees of up to £120,000, with Sunday Times reporters posing as lobbyists for a foreign firm. All four strenuously deny any wrongdoing.
