The deputy prime minister’s comments came as senior Conservatives and Liberal Democrats engaged in a weekend of sparring over the imminent referendum on scrapping the first-past-the-post electoral system. While some observers believe the immigration spat has been ramped up to highlight differences between the coalition partners ahead of the local elections, there was genuine anger among senior Lib Dems over an intervention in the alternative vote debate by George Osborne.
The chancellor said at the weekend that the Electoral Reform Society – which has contributed £1.1m to the Yes campaign – would benefit from a switch to AV through ERSL, its commercial arm, which runs election services.
That drew an angry response from Paddy Ashdown, former Lib Dem leader, who said Mr Osborne’s “bizarre” claim offered a prime example of why British politics needed to change. Mr Clegg also went on the attack, telling the BBC there was a “lot of mudslinging going on”.
Mr Cameron defended his chancellor against accusations of dirty tricks, saying he had merely represented “the facts”. But he was also at pains to insist the coalition would remain strong whatever the result of the May 5 referendum.
There are fears that a No vote will undermine Mr Clegg’s position in his party and encourage soul-searching about what Lib Dems are gaining from being in government. The No campaign has a six-point lead, according to a ComRes survey for the Sunday Mirror/Independent on Sunday.
Some weekend reports suggested Mr Cameron was preparing to offer Mr Clegg concessions in the event of a No vote, such as allowing peers to be voted into the House of Lords under proportional representation.
Mr Cameron would similarly have to face the fury of Tory grass roots supporters if Mr Clegg prevailed.
The prime minister on Monday shares a platform with John Reid, former Labour minister, to oppose AV. Ed Miliband, Labour’s leader, will join Vince Cable, Lib Dem business secretary, to argue for change.
Mr Cable accused Mr Cameron last week of making “unwise” comments about immigration. Mr Clegg sought to play down a split on Sunday, but insisted Mr Cameron’s target was not agreed policy. “It is not government policy to pursue a numerical target,” he said.
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