Nicola Sturgeon jeered in TV debate after suggesting Scotland will hold another referendum

Another referendum on Scotland’s independence could be back on the political agenda within a year, Nicola Sturgeon has admitted.

The SNP leader, dropping her guard during the televised debate in Edinburgh, hinted that her party could seek another vote on whether Scotland should leave the Union soon after 2016.

Her predecessor Alex Salmond insisted the referendum was a “once in a generation” event.

During the live broadcast that featured the four leaders of Scotland’s main political parties, Ms Sturgeon insisted that the general election would have no influence on whether another referendum was held. But asked what would happen after 2016’s Scottish parliamentary election, she replied: “That’s another matter.”

When the studio audience jeered, she said the decision would ultimately rest with Scottish voters.

The answer may haunt Ms Sturgeon over the remaining weeks of the general election campaign. So far her party’s strategy has been to stress its “friendship” with the rest of the UK by painting a picture of a “progressive” alliance at Westminster.

Her answer will be seized upon by Labour in Scotland.

Ruth Davidson, the leader of the Scottish Conservatives, had earlier sought to reassure No voters in the referendum that the issue would not be revived. She said: “No deals with the people who would break up Britain”.

Ms Sturgeon was forced to fend off attacks from her Labour counterpart Jim Murphy, Scottish Liberal Democrat leader Willie Rennie and Ms Davidson.

In one early clash, Mr Murphy tried to suggest that SNP voters would be better off simply voting Labour, by repeatedly asking Ms Sturgeon if she wanted Mr Miliband to be the next prime minister. She replied: “I don’t want David Cameron to be prime minister – I’m offering to help make Ed Miliband prime minister.” Mr Murphy retorted: “Nicola, we don’t need your help. What we need is people north and south of the border coming together to kick out an out-of-touch government.”

On the renewal of the UK’s Trident nuclear deterrent, one of the key policy issues that divides the SNP from Labour, Ms Sturgeon said the 190 nations in the world that did not have nuclear weapons were no less safe.

She said her party’s rejection of Trident meant that Scotland – and the UK – would be able to “lead by example”.

A hint of the difficulties Labour and the SNP could face if they try to reach agreement after 7 May, came during heated exchanges between Murphy and Sturgeon on future spending cuts.

Sturgeon said exchanges between the Tory leader, Ruth Davidson, and Murphy were “manufactured divisions” and accused Murphy of walking through the lobby in Westminster “hand in hand” with the Conservatives during last month’s debate on the budget.

Sturgeon told the audience that Labour were preparing for £30bn worth of cuts. “You cannot be anti-austerity and propose more cuts.”

Murphy’s attack received applause when he said, “You are entitled to your opinion, but not to your own facts.”

SNP leader and First Minister Nicola Sturgeon

“I’ve said to Ed Miliband and I’ll say to Jim Murphy, that if there is an anti-Tory majority in the House of Commons after the election, even if the Tories are the biggest party, we will work with Labour to keep David Cameron out of Downing Street.”

Scottish Labour leader Jim Murphy

“Nicola, we don’t need your help. We need people north and south of the border… coming together to kick out an out-of-touch government.”

Scottish Conservative leader Ruth Davidson

“I promise to fight head, heart, body and soul to honour the referendum vote and will not do any deal with a party that wants to break the Union.”

Scottish Liberal Democrat leader Willie Rennie

“We have got the economy back on track, and we have done it fairly.”