LONDON - Britain's ruling Labor party suspended a senior lawmaker and a top aide to the opposition leader stepped down Thursday in a widening sleaze scandal that is alienating voters.

Prime Minister Gordon Brown and his Conservative rival David Cameron are under pressure to crack down on excessive expense claims in their parties after a series of damaging leaks that threaten to overshadow European and local elections next month.

Conservative legislator Andrew Mackay resigned as senior political adviser to Cameron after a review of his expenses revealed an unacceptable situation, a spokesman for Cameron said.

Brown said later that his party had suspended Elliot Morley, a former agriculture minister reported to have filed 16,000 pounds ($24,200) of expense claims for a mortgage he had already paid off.

They are the first politicians to be disciplined in the row over political perks that analysts say may either put voters off taking part in the June 4 polls or encourage them to choose fringe groups like the far-right British National Party.

In a separate scandal, a parliamentary watchdog said two Labor members of the upper House of Lords should be suspended after a newspaper alleged they were prepared to take large sums of money for trying to get laws amended.

Britain's 646 legislators receive an annual salary of almost 65,000 pounds, but also claimed 93 million pounds in allowances last year, an average of 144,000 pounds each.

The Daily Telegraph newspaper has been embarrassing both major parties with daily revelations about how lawmakers have claimed for expenses such as cleaning swimming pools and moats, installing a chandelier and buying manure for the garden. The disclosures have infuriated voters at a time when Britain is in deep recession and many are losing their jobs.

The Sunday Times newspaper, which sent reporters posing as lobbyists to talk to two Labor Lords, Thomas Taylor and former energy minister Peter Truscott, alleged they asked for as much as 120,000 pounds to get a law on business taxes amended.

The watchdog found that the pair had broken a parliamentary code of conduct and recommended they be suspended for up to six months. The upper house will vote on the recommendation next week. If it goes ahead, they would be the first Lords suspended since 1642, news reports said.

Labor and Conservative politicians, including several government ministers, have been rushing to repay questionable expense claims. More than 20 lawmakers have so far pledged to repay nearly 130,000 pounds, the BBC said.