Nick Clegg

The UK is "trapped" in a political system which could throw up "eccentric outcomes" and requires change, Liberal Democrat leader Nick Clegg has said.

"I don’t think after this election it will ever be possible to put the genie back in the bottle," he added.

Tory leader David Cameron said he was happy with the current voting system but did not rule out changing it.

Home Secretary Alan Johnson said on Sunday Gordon Brown saw a need for "dramatic change" to the constitution.

Opinion polls continue to suggest no party will gain an overall majority in the election on 6 May, which would lead to a hung parliament.

Mr Clegg, who favours a proportional representation voting system, said the obvious "unfairness" of the present set-up meant "electoral reform is a first step of any government of any composition".

"The way in which politicians may need to speak to each other after the general election will be shaped, and has to be shaped, entirely by two things.

David Cameron

"Firstly, by the result of the election… and, secondly, by the priorities that each of the parties set out.

"I have tried to be quite clear that, it seems to me, that there are some circumstances which, it seems to me, will strike most people in this country as either unfair or very fair."

Mr Cameron claimed the Lib Dems were "in complete muddle and confusion" and "too often away with the fairies".

"One of the dangers of a hung parliament is that you wouldn’t get change," he said.

"Proportional representation doesn’t put power in the hands of people; it puts power in the hands of politicians.

"They can haggle and scheme and negotiate. That’s not what it should be about. Elections should be decisive events."

The Conservative leader gave no firm commitment that he would never preside over a change in the voting system, the BBC’s chief political correspondent, Laura Kuenssberg, said.

Gordon Brown and Alan Johnson

On Sunday Home Secretary Alan Johnson told the BBC it would be a "difficult" situation, should Labour finish third in terms of the popular vote.

"Look, it doesn’t take a genius to think that if you are third in the popular vote, then… you are not best-placed to deal with it," he said.

He said after the election there would be "a debate on proportional representation on the electoral system".

Health Secretary Andy Burnham said Labour would "work with what the country decides".

"Let’s just wait and see what the country says," he told Sky News on Monday.

"It is not votes cast, it is seats in the House of Commons that will determine what happens, and people will have to deal with the situation as it arises."

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