The First Minister will go to London for talks with politicians working to thwart the Prime Minister’s Brexit plan, and said she hopes to sit down with Labour and others to formulate an alternative.

The call for unity came as Mr Corbyn faced criticism for again appearing to play down the prospects of a referendum on the terms of Brexit, claiming it was “not an option for today” and refusing to say how he would cast his ballot in a so-called “people’s vote”. Ms Sturgeon described Mrs May’s draft agreement as a “blindfold Brexit” that lacked clarity on the UK’s future relationship with the EU and confirmed SNP MPs would vote against it in the Commons.

“If the House of Commons says we want to go down the road of single market and customs union membership, we want more time to take this back to the people of the UK in another vote, we need an extension of Article 50 – if there is a clear change of direction – then I believe the EU 27 would be prepared to look at that,” the First Minister said on the BBC’s Andrew Marr show.

“But that means those who don’t want this deal coming together.

“Those who don’t think the Prime Minister’s deal is the right way to go have now a responsibility to come together and coalesce around an alternative.

“I will seek to have discussions this week with other parties to get us into that position.”

The First Minister said she was keen to talk to Mr Corbyn “and whoever else” in the Commons when she visits London.

Labour peer Lord Foulkes said the SNP and Labour leaders should meet. “We need to build a broad front on the way forward, which I hope would be a people’s vote,” he said. Scottish Labour MEP Catherine Stihler said: “Support is growing for a people’s vote, and there is an opportunity for Labour to get fully behind this and campaign to stop a reckless and damaging Brexit.

“This is a time for strong leadership in the interests of the workers who our party represents.

“I encourage Jeremy to engage with other party leaders, including Nicola Sturgeon, to address the Brexit crisis.”

East Lothian MP Martin Whitfield said: “For Theresa May to understand that all of the parties that are in opposition are as one on this is useful for her to know.

“There is an opportunity there for people to talk… that’s what needs to happen. The time has come to say that [a people’s vote] is what the majority of the country want.”

He added: “If ever there was a time for people to start talking, now is it.”

Last week Mr Corbyn raised hopes that opposition parties would present a united front when he joined Ms Sturgeon in signing a letter demanding MPs be able to amend the motion that puts the Brexit deal to a Commons vote.

However, despite party policy stating that Labour will pursue a second EU referendum if attempts to change the deal or force a general election fail, Mr Corbyn poured cold water on calls for Labour to support a people’s vote, saying it was “an option for the future” but “not an option for today”.

In an interview with Sky’s Ridge On Sunday, he also told how his party couldn’t stop Brexit “because we don’t have the votes in Parliament to do so.

“There was a referendum in 2016, a majority voted to leave the EU, there are many reasons why people voted.

“I don’t think you call a referendum and then say you don’t like the result and go away from it. You’ve got to understand why people voted and negotiate the best deal you can.”

Asked about calls for a second referendum, Mr Corbyn said: “It’s an option for the future but it’s not an option for today, if there was a referendum tomorrow what’s it going to be on, what’s the question going to be?”

Asked which way he would vote in such a referendum, he said: “I don’t know how I am going to vote, what the options would be at that time.”

The Labour leader will appeal to business to back his plan for a Brexit deal in a speech to the CBI conference in London today.

Arguing that Labour can secure a deal with closer ties to the EU market and better protections for workers’ rights, Mr Corbyn will say: “The government is trying to force a bad deal that doesn’t meet our country’s needs by threatening us all with the chaos and serious damage to our economy of a no-deal outcome.

“The Prime Minister knows that no-deal isn’t a real option. Neither the Cabinet nor Parliament would endorse such an extreme and dangerous course.”

Jeremy Corbyn urged to meet Nicola Sturgeon and form united front for new Brexit vote