IAN Blackford has warned the Prime Minister that “Scotland will act” if Westminster fails to do what is in the interest of the whole of the UK.

In the first Prime Minister’s Questions since the Speaker of the House’s dramatic intervention, and Theresa May’s subsequent request for an extension to Article 50, Blackford began by asking if she agreed with her de facto deputy that her actions were “downright reckless”.

READ MORE: EU warn Theresa May's Article 50 extension may be unacceptable

The SNP’s leader at Westminster said: “Six days ago David Lidington said that ‘In the absence of a deal, seeking such a short and, critically, one-off extension would be downright reckless’.”

He then asked if she agreed with Lidington that this was an accurate description of her decision to request an extension from the EU.

May responded that it was time for the House to deliver Brexit for the British people.

Blackford replied: “We need to reflect that her deal had the biggest defeat in parliamentary history. She brought it back, it had the fourth-biggest defeat in parliamentary history. Her deal has failed. This House has voted against no deal.

“Once again the Prime Minister is acting in her own self-interest, not in the interest of the whole of the UK.

“The Prime Minister has failed, this place has failed and Scotland is watching.

He added: “The only way forward now, Mr Speaker, is to put the decision back to the people. Will the Prime Minister give the people a say in such a referendum?

“Mr Speaker, the people of Scotland deserve a say on their future. If Westminster fails, Scotland will act.”

May responded that there is “an enormous responsibility” on MPs to deliver on the result of the 2016 referendum, and that it was “imperative” to do so for people to have trust in their politicians and faith in Parliament.

Earlier in the session, May told MPs that she intends to table the withdrawal agreement which she has negotiated with the EU for a third time in the Commons next week, in the hope of overturning the massive defeats inflicted on it in January and March.

Brussels has made clear that any extension of the Article 50 negotiation process beyond the end of June would require the UK to elect MEPs to take their seats in the next European Parliament in July.

May told PMQs: "The idea that three years after voting to leave the EU, the people of this country should be asked to elect a new set of MEPs is, I believe, unacceptable.

"It would be a failure to deliver on the referendum decision this House said it would deliver.

"I have therefore this morning written to President Tusk ... informing him that the UK seeks an extension to the Article 50 period until June 30."

May will formally make her request to the European Council summit in Brussels on Thursday, where the unanimous approval of all 27 remaining member states is required for any extension.

In her letter to Tusk, May said that it remains the Government's policy to take the UK out of the EU "in an orderly manner" on the basis of the Withdrawal Agreement and Political Declaration agreed in November and supplemented by documents agreed with Commission president Jean-Claude Juncker last week.

READ: Theresa May's letter to Donald Tusk asking for Brexit delay

The Agreement was rejected by 230 votes in January and 149 votes earlier this month.

And Commons Speaker John Bercow this week said he would not allow the same motion to be brought again during this session of Parliament, unless it was substantially changed.

But May told the Commons: "The Government intends to bring forward proposals for a third meaningful vote.

"If that vote is passed, the extension will give the House time to consider the Withdrawal Agreement Bill. If not, the House will have to decide how to proceed.

"But as Prime Minister, I am not prepared to delay Brexit any further than June 30."