NICOLA Sturgeon has said she would "very much" like to hold a second independence referendum within the next five years.

Launching the SNP's election manifesto, the First Minister received rapturous applause from 1400 supporters when she spoke of her desire to see a swift re-run of the 2014 poll.

The manifesto made no firm pledge of a referendum if, as the polls indicate, the Nationalists form a majority at Holyrood after May 5.

Addressing party activists at a packed Edinburgh International Conference Centre, Ms Sturgeon conceded they must "earn the right" to stage a second referendum.

But she said a poll would be held "when we succeed" in winning sustained majority support for independence.

She said a campaign would start this summer to win over people who voted No two years ago.

READ MORE: Nicola Sturgeon: SNP must earn right to propose second indyref

Her comments draw sharp criticism from opponents, with the pro-UK campaign group Scotland in Union claiming they left the country "in constitutional limbo".

The SNP described its policy platform as a "manifesto for the next generation".

It included plans to widen access to university to students from poorer backgrounds, which Ms Sturgeon admitted "could be controversial along the way" if resisted by principals.

She also announced plans to channel hundreds of millions of pounds directly to headteachers in a bid to close the "attainment gap" between pupils from better and less well off backgrounds.

READ MORE: Ruth Davidson: Nicola Sturgeon's refusal to rule out second independence referendum is 'beneath her'

New parents will receive a "baby box" of essential items, in an idea borrowed from Finland, and over the next five years, free childcare will be doubled to 30 hours for three- and four-year-olds and some two-year-olds.

Ms Sturgeon made only a passing reference to tax - an issue that has dominated the election debate - in her speech, confirming she would not pass on in full George Osborne's income tax cuts for higher earners south of the Border.

Her biggest cheers, however, came when she said: "There is not a day goes by that I am not asked if there will be a second independence referendum in the next parliament.

"Well, my answer to that in one sense is simple: I would like that very much."

But she said her party would have "no right" to propose a second referendum unless it could support a majority of Scots to support independence.

The manifesto also said a "significant and material change of circumstances," could trigger a second vote.

Asked later whether Britain's exit from the EU, in the face of most Scots voting to remain, would automatically lead to a referendum, she said: "These are judgements I'll have to take if that scenario arises."

READ MORE: SNP manifesto 'will not include independence vote pledge'

Alastair Cameron, director of Scotland of Union, said:

"This manifesto leaves us in constitutional limbo when we should be moving on."

Scottish Conservative leader Ruth Davidson said:

"Nicola Sturgeon had the chance today to set a course that leaves the division of the referendum behind us.

"Instead she has made it clear she wants to put Scotland through five more years of rancour over the constitution."

Willie Rennie, the Scottish Liberal Democrat leader, said: "The truth is that for the SNP, the timing of any second referendum is down to the opinion of Nicola Sturgeon."