����ý

Deputy Prime Minister Nick Clegg has rebuffed calls backed by 44 Tory MPs for the date of the referendum on voting reform to be moved.

Elections for the Welsh Assembly, the Scottish Parliament, the Northern Ireland Assembly and some English councils are all also due for 5 May.

The MPs fear differing turnout across the UK and overshadowing of the debate.

Mr Clegg said it was "disrespectful" to suggest voters "could not make two different decisions at the same time".

He said everyone in Scotland, Wales and Northern Ireland, plus 80% of people in England were already due to vote on 5 May 2011, so it would save them having two trips and cut costs by £17m.

But senior Tory backbencher Edward Leigh told Mr Clegg as he took deputy prime minister's questions, that the referendum should be on a different date so there could be a "proper debate" about the issue.

Earlier a Downing Street source had called reports of a revolt against electoral reform "a little exaggerated".

Former cabinet ministers Peter Lilley, John Redwood and Sir Malcolm Rifkind have signed a Commons motion of complaint about the referendum date.

Also among the signatories to the document, tabled by Tory MP and former defence spokesman Bernard Jenkin, is former shadow home secretary David Davis.

'Odd result'

Mr Jenkin suggested ministers had room to change the date as it was not part of the coalition agreement itself.

"Therefore it is of less status than, for example, a point of principle," he told ����ý Radio 4's World at One.

The choice of date, he said, should not be determined by the cost of staging the referendum but on whether it would provide a "true and fair test of public opinion".

Holding it on 5 May could lead to an "odd result" because of wide variations in turnout in different parts of the country, he added.

"One has the suspicion that Nick Clegg wants it on this date to disguise the fact that, out there, there is an awful lot of apathy about changing the voting system."

Under the post-election agreement reached by the Conservatives and Liberal Democrats, the coalition is committed to hold a referendum on adopting the "alternative vote" (AV) system.

This allows voters to rank candidates in their constituency in order of preference.

Anyone getting more than 50% of first-choice votes in the first round is elected, otherwise the candidate with the fewest votes is eliminated and their backers' second choices allocated to those remaining. This process continues until a winner emerges.

Prime Minister David Cameron, who opposes getting rid of the current "first-past-the-post" system, will campaign against such a change. His deputy, the Lib Dem leader Nick Clegg, will push for the reform.

It is feared the issue will cause inter-party strife.

The motion submitted by the 44 Tory MPs argues that referendums on issues of national importance should be held "in isolation", as turnout would be "artificially inflated" in parts of the country where elections are being held.

It urges the Electoral Commission - which has said a referendum is "deliverable" on 5 May but there are some "risks" attached to the date - to make the final ruling.