A hard Brexit is “off the table,” Nicola Sturgeon has insisted, as she said the General Election result meant that the issue of the UK leaving the EU could not “continue to be cooked up by a Tory cabal” but had to be opened up to more voices.

The First Minister’s intervention came within minutes of No 10 brushing aside her call for a new cross-party "four nation" approach to the forthcoming Brexit negotiations.

Theresa May’s spokesman, asked if the Prime Minister thought Ms Sturgeon’s proposal was a good one, replied: “We gave a commitment right at the very outset of this process to consult with the devolved administrations and that remains the case."

The FM wants membership of the European single market and the customs union to be "at the heart" of a new way forward, with the rights of EU nationals living in the UK guaranteed with immediate effect.

But when asked if there would be any change to the Tory administration’s approach to Brexit, the PM’s spokesman made clear that the UK Government would continue to seek to secure the best possible deal for the whole of the UK, adding there were “no change to these plans”.

The spokesman made clear there would be “discussions in cabinet” but noted how David Davis, the Brexit Secretary, had set out the Government’s plans clearly and “there would be no change to those”.

Asked if Mrs May was open to changes to the Brexit strategy, he added: “Our position has been set out and that is where we are.”

After a photocall for the SNP’s 35 MPs at Westminster, Ms Sturgeon said the UK Government’s approach to Brexit could no longer stand.

“The process should be opened up to more voices, a cross-party, four nation approach and that approach must be centred on retaining our position in the single market. As the third biggest party, these are the priorities these MPs are going to get to work on.”

But when it was pointed out how Mrs May had already dismissed her suggestion for a “four nation” approach to the Brexit talks, the SNP leader replied: “No 10 has been behaving to the bemusement of everybody across the country as if nothing has changed in the election; everything has changed.

“It’s no longer acceptable for the Prime Minister and the Government to try to operate the way they were doing before the election. They asked for a mandate for a hard Brexit and they failed to get that mandate. So hard Brexit is now off the table and has to be off the table.”

She went on: “The idea that Brexit can continue to be cooked up by a Tory cabal is not acceptable. There have to be more voices involved and there has to be a fundamentally different approach and as the third biggest party in the House of Commons that’s what these MPs will be working to secure.”

Later, Ruth Davidson, who attended the Conservatives’ political cabinet in Downing St, intervened to express a similar sentiment, that there had to be wider involvement in the Brexit strategy than just the Conservatives.

She told the BBC the Tories needed to work with people within the House of Commons and those outwith "to ensure that as we leave the EU we have a Brexit that works for the economy and puts that first".

The Scottish Tory leader went on: "We do have to make sure that we invite other people in now. This isn't just going to be a Tory Brexit, this is going to have to involve the whole country."

Ms Davidson stressed how Mrs May and her cabinet colleagues had given "a real recognition" to her suggestion.

"We can make a big, bold offer that brings the country with us, that brings people in from the other side of the aisle in the House of Commons but also brings people in from outside the Commons too," she added.

Meantime, Willie Rennie, the Scottish Liberal Democrat leader, at Westminster to welcome his four new MPs to the Commons, expressed similar sentiments, saying Mrs May should “abandon the embryonic alliance with the DUP”.

He added: “It should not be the case that the Conservatives and the DUP have the final say as to what is acceptable on Brexit. There needs to be a much more cross-party consensus because Theresa May’s proposal for a hard Brexit had been rejected…So, therefore, she needs to reach out to all the other parties to work together to come up with a new proposition.”