General Election 2015: Lib Dems would only join with Tories again if they drop £12bn welfare cuts, says Nick Clegg

Nick Clegg could give David Cameron the go-ahead to hold an in/out EU referendum in post-election talks on another coalition, but in return would demand the Conservatives scrap their planned £12bn of welfare cuts.

The possible trade-off emerged on Wednesday after Mr Clegg launched the Liberal Democrat manifesto with a pledge to “fight tooth and nail” for the five non-negotiable demands on its front page. They are balancing the national budget in a fair way; guaranteed education funding "from cradle to college"; an increase to £12,500 in the personal tax allowance; £8bn extra for the NHS and five green laws to protect the environment. He said they enjoyed a “near religious status.”

Senior Lib Dems added a sixth demand, saying the party would not join another coalition with the Tories unless they abandoned plans for deep cuts in the welfare budget. Instead, the Tories could back Lib Dem proposals to raise taxes on the rich, even though the Tory manifesto says no tax increases are needed to clear the deficit.

Mr Cameron would tell Mr Clegg that his key non-negotiable “red line” would be the 2017 referendum he has promised on Europe. He would not secure the backing of Tory MPs for a second coalition if he tried to drop the referendum. Officially, the pro-EU Lib Dems oppose an “arbitrary timetable” for a public vote that could create uncertainty for British business. They say a referendum should take place only if Britain proposed to transfer more powers to the EU.

But some Lib Dem sources believe the party would have to let Mr Cameron’s referendum go ahead in order to secure a post-election deal. The move would be controversial and senior figures including Vince Cable and Tim Farron have opposed the idea. But, significantly, Mr Clegg has not ruled it out.

Lib Dem officials insisted that no decisions had been made, saying it would be pointless to discuss such an agreement until the party knew how many votes and seats it had won on May 7.

The Deputy Prime Minister unveiled what he called a manifesto for government not opposition – a rebuke to activists who say his party should “recharge its batteries” after five gruelling years and spurn another coalition. The blueprint runs to 155 pages and 33,000 words.

Claiming that Mr Cameron and Ed Miliband knew they could not win a majority, Mr Clegg argued: “What really matters is who they will have by their side”. He told voters: “Ask yourself this: do you want Nigel Farage walking through the door of Number 10? It could be Alex Salmond. Or it could be me and the Lib Dems.”

In a scathing reference to his two potential partners, Mr Clegg said: “The Lib Dems will add a heart to a Conservative government and we will add a brain to a Labour one.” He added: “We won’t allow the Conservatives to cut too much and jeopardise our schools and hospitals. And we won’t allow Labour to borrow too much and risk our economy again.”

There was bad news for his party in a ComRes poll for ITV News last night in its South West heartland, where it is defending 14 seats. There has been a 13-point swing from the Lib Dems to the Conservatives since 2010, which could hand Mr Cameron’s party all of the these seats.

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