Labour and the Liberal Democrats have accused Nicola Sturgeon of a sham search for alternatives to independence as they confirmed they will oppose proposals for another referendum.

A furious row erupted after Scottish Lib Dem leader Willie Rennie claimed Ms Sturgeon had "betrayed" her own pledge made in the wake of the shock vote to leave the European Union.

"From that moment on, she has talked about little else (except independence),” he said, consigning a cross-party consensus on the issue “to the dustbin".

READ MORE: Labour and Lib Dems to oppose second independence referendum plans

The Scottish Government said that the First Minister was committed to exploring all available options and accused Mr Rennie of publicity seeking.

The argument follows speculation that Ms Sturgeon will set out legislation for a second referendum next week.

The Scottish Conservatives have already said they oppose another vote, meaning the SNP leader will have to rely on support from Green MSPs to get a Bill through Holyrood.

After the Brexit vote Ms Sturgeon announced that ministers would begin work on proposals for another referendum, to be held if it proved the "best or only way to protect our place in Europe".

READ MORE: Labour and Lib Dems to oppose second independence referendum plans

Both Labour and the Lib Dems backed a Holyrood motion authorising the Scottish Government ministers to examine how Scotland maintains its links with the EU.

At the time Ms Sturgeon assured MSPs it was “not a vote for a referendum on independence".

Mr Rennie said: "From that moment on, she has talked about little else, betraying those words she uttered in Parliament and consigning the consensus to the dustbin."

Independence was the "only solution" she had offered, while showing a “remarkable degree of enthusiasm” for Brexit, he said.

"I know her activists believe this is a golden opportunity to win independence but she has a responsibility to lead the country, not just her party," he added.

Scottish Labour leader Kezia Dugdale also made clear her opposition to another vote.

She said that hr party’s manifesto was “very clear, we're opposed to a second referendum in the lifetime of this parliament".

READ MORE: Labour and Lib Dems to oppose second independence referendum plans

Her comments also appeared to slap down Owen Smith, the Labour leadership candidate who said earlier this week that he would not oppose a second referendum.

A spokesman for the First Minister said: "Willie Rennie is profoundly mistaken... the position the First Minister laid out on June 24, and which Mr Rennie backed in a parliamentary vote, is unchanged.

"The First Minister is clear that protecting Scotland's interests and our place in Europe is her starting point.

“As recently as last week, she made clear that the Scottish Government will use whatever influence it has to shape the best outcome for the whole UK...however, she has also been clear that the option of independence should be on the table if it becomes clear that it is the best or only way of safeguarding our interests.”

He also accused Mr Rennie of seeking attention for his “increasingly irrelevant party”.

READ MORE: Labour and Lib Dems to oppose second independence referendum plans

Ross Greer, the Scottish Greens external affairs spokesman, accused Mr Rennie of flouncing off “in a huff” .

But he added that “all avenues” available to maintain on Scotland’s links with the EU must be exhausted.

The Scottish Conservative leader Ruth Davidson has called on the SNP to give up plans for a second independence vote.

She said that figures published earlier this month showing Scotland had a £14.8bn deficit last year showed "the cost of independence".

Earlier this month Ms Sturgeon said that the "argument that the UK is somehow a safe harbour for Scotland is no longer true".

More than 60 per cent of Scots voted to stay in the EU.