Nicola Sturgeon has stepped up pressure on Theresa May to give ground over Brexit, saying the SNP “won’t be complicit in more time wasting” by joining futile discussions.

The First Minister said there was no point in talking to the Prime Minister if she stuck rigidly to her existing red lines, regardless of the landslide defeat of her Brexit deal on Tuesday.

SNP Westminster leader Ian Blackford held a preliminary talk with Mrs May on Wednesday evening, but told her he could not enter a full discussion without concessions.

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Ms Sturgeon wants Mrs May to rule out a No Deal Brexit, extend the Article 50 withdrawal process, and to consider a People’s Vote.

Scottish Secretary David Mundell told BBC Radio Scotland this morning that “everything was on the table” for cross-party talks.

However Mr Mundell also excluded “arrangements that seek to stop Brexit”, including a People’s Vote.

Ms Sturgeon responded in a tweet: “So everything is not on the table. PM’s offer of talks is a promise to listen, but only if we all agree with her.

“@theSNP won’t be complicit in more time wasting. Rule out no deal, be prepared to extend Art 50 and agree to at least consider another referendum - then we’ll talk.”

A Scottish Government source said: “The Prime Minister has got to start erasing some of her red lines,” a source said. Unless she does that it’s pointless.”

Jeremy Corbyn has said Labour will not even have a preliminary discussion with Mrs May unless she rules out a No Deal Brexit.

With the Prime Minister appearing unwilling to budge despite the overwhelming rejection of her plan, MPs may take the process out of her hands in parliament next week.

Mr Mundell told Good Morning Scotland the Prime Minister was willing to discuss “anything” in talks with other parties, but they would "not be a cover for trying to stop Brexit".

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He also Mr Corbyn’s demand to take No Deal off the table was “the wrong starting point”, adding he not believe the EU would extend the timetable for the Article 50 talks.

He admitted he had "not anticipated the scale” of Tuesday 230-vote defeat for Mrs May.

Speaking about the Prime Minister, Mr Mundell said: "She's not going down a route to stop Brexit, she is willing to discuss anything people want to put on the table to get us to a point where we can get a majority in Parliament to support a deal to allow an orderly Brexit.

"Everything is up for discussion but what isn't going to be an outcome is arrangements that seek to stop Brexit, which I believe the People's Vote is designed to do.

"Not only that it would be extremely divisive in our country. We've had a People's Vote, people voted across the United Kingdom and a United Kingdom-wide vote to leave the EU, and we are respecting the result of that and seeking to deliver Brexit, but an orderly Brexit.

"That's what discussions are about. Of course people can raise any issues that they want, but the discussions are not a cover for trying to stop Brexit."

Mr Blackford also told BBC Radio Scotland: "We will accept our responsibility to engage positively in talks but it has to be on the basis that there is a positive engagement.

"I've written to the Prime Minister overnight and said that what has to happen is there has to be an agreement that we can have discussions about extending Article 50, about taking no deal off the table, and about having a People's Vote."

He added: “I actually think, on the basis of where we are, a People's Vote is the right way to go, I think on the basis of the paralysis in Parliament we ought to put that back to the people.

"I'm not saying that is a position the Prime Minister would support but if she is serious about engagement, if she is serious about trying to find a way through this, she has at least got to have that discussion about these options."

Tory Party chairman Brandon Lewis has also insisted that the Government did not believe a People's Vote was "the right way to go".

He also said ministers were determined the UK should have an independent trade policy outside the EU - adding this ruled out any suggestion of remaining in the customs union.