A NEW law could be brought forward to expel convicted peers from the House of Lords, Nick Clegg has signalled.

The Deputy Prime Minister told MPs a planned bill to recall or sack errant MPs, to be introduced next year, could incorporate measures to reform the size of the second chamber at Westminster.

Mr Clegg said he still regretted his hopes for an elected Lords had been dashed, but said: "Having said that, where there are minor, technical house-keeping changes which might be deemed necessary in the House of Lords – kicking out crooks or people who don't attend or extending the voluntary retirement scheme.

"Where that needs legislative backing, of course we will look to incorporate that in wider bills that we are going to advance, for instance, on the recall of MPs from the Commons."

Under present rules, peers convicted of a crime can return to the Lords, in contrast to MPs who are disqualified if they are jailed for more than a year.

Mr Clegg's suggestion could see the expulsion of Lord Watson, who spent time in prison for fire-raising, Lord Archer, who was jailed for perjury, and fellow Tory Lord Black who served more than three years in the US for fraud.

Liberal Democrat peer Lord Steel previously tabled a bill to allow the voluntary retirement of peers as well as the forced retirement of those who did not attend enough sessions or were convicted of crimes. Tomorrow, he will give evidence before the Commons Political and Constitutional Reform Committee on Lords reform.

Mr Clegg's endorsement came as John Bercow, the Commons Speaker, suspended the issuing of new Commons passes to staff working for all-party groups amid concerns they are being used for political lobbying.

Mr Bercow said there was a need for "urgent and effective action" after allegations that a Tory MP, two Labour peers and an Ulster Unionist peer were prepared to exercise political influence in exchange for cash from undercover reporters posing as lobbyists, allegations they all deny.

No 10 has announced a bill to create a register of lobbyists will be brought forward before MPs go for their summer break in July.

However, the row over extra measures in the bill – the ending of self-certification for trade unions and a crackdown on third-party funding – rumbled on.

Labour and the unions have branded as "cynical" the decision by David Cameron to include these measures in the register of lobbyists bill, saying they are a direct attack on trade unions and a bid to curb Labour's spending power.

The Prime Minister's spokesman said all three measures had been "agreed across Government."

However, a senior LibDem source said: "I can absolutely categorically tell you the details have yet to be agreed.

"The Liberal Democrats will not sign up to anything that is tailored only for the trade unions; that is not what this is about. This is about ensuring third-party organisations [are subject to a] more transparent process."

Karen Jennings for Unison, said: "These proposals are typical of the Tories playing the same tired old anti-union card."