Coalition heavyweights clash on AV

Coalition tensions over voting reform escalated today as David Cameron was accused of peddling "nonsense" by a senior Liberal Democrat.

Party president Tim Farron charged him with deploying "very silly" arguments as Mr Cameron stepped up opposition to the alternative vote.

The premier warned that if AV were approved in the May 5 referendum, Britain would be "sleepwalking" towards a system that would weaken democracy. He claimed that with AV, "people who vote for extremist parties have their vote counted more times, candidates who come third can end up winning... it's a more complicated system, it isn't necessarily more fair."

Mr Farron said: "It is a very, very silly set of arguments riddled with nonsense. The only people who should worry about a yes [to AV] vote are the BNP, who'd be locked out for ever, or lazy MPs."

Under AV, candidates are ranked in order of preference. Second preferences are taken into account until someone gets 50 per cent of the vote.

The Lib-Dems back change but the Tories want to keep first-past-the-post. Labour is split.