THERESA May should “accept defeat” on her Brexit plan and grab the offer from Brussels of a rethink, Nicola Sturgeon has insisted, as MPs attempt to find a Commons consensus on Britain's EU withdrawal in a proposed vote next week.

After the Prime Minister suffered a third parliamentary defeat and ahead of a move tonight to delay Brexit - with the Government setting out the options of either a short three-month extension or a longer, possibly two-year, extension - Donald Tusk, the European Council President, intervened via social media, tweeting he would "appeal to the EU27 to be open to a long extension if the UK finds it necessary to rethink its #Brexit strategy and build consensus around it".

His words were seized on by the First Minister, who said: “Instead of the PM pathetically using this[issue of extension] to bully MPs into accepting a profoundly bad, already twice defeated deal, we should grab it with both hands and get out of the #brexit mess."

Ms Sturgeon added: "If you are a Brexiteer, what does it say about your project if it has to be founded on a deal that a majority believes to be fundamentally flawed. That cannot be the way to proceed, which is why PM should accept defeat, change course and accept this opportunity for a rethink."

Also in response to Mr Tusk's suggestion for a long extension, Guy Verhofstadt, the European Parliament's Brexit co-ordinator, tweeted: "Under no circumstances an extension in the dark!"

The former Belgium Prime Minister added: “Unless there is a clear majority in the House of Commons for something precise, there is no reason at all for the European Council to agree on a prolongation. Even the motion tabled for this evening by the UK Government recognises this."

Simon Coveney, Ireland’s deputy Taoiseach, told RTE radio: "If you have a long extension of, say, 21 months to the end of 2020 - whatever the period would be - then Britain has a legal entitlement to have representation in the European Parliament," and so must take part in the May EU elections.

As the Brexit debate got underway in the Commons, Mrs May was chairing a special political Cabinet meeting in Downing Street.

After the defiance of 13 ministers, including four in Cabinet, on Wednesday night’s vote, tensions were expected to be high.

In the Commons chamber, a row erupted over the selection of amendments by the Commons Speaker after he declined to allow one, Amendment B, ruling out a People’s Vote to be debated and voted on.

The amendments John Bercow selected are:

*Amendment H, tabled by Independent Group MP Sarah Wollaston, which seeks an Article 50 extension to stage a second referendum with Remain and Parliament's preferred Brexit option on the ballot paper;

*Amendment I, tabled by Labour's Hilary Benn and the Tories’ Oliver Letwin, which seeks to allow MPs to take control of the Brexit process by staging a series of indicative votes to find which Brexit approach could command a majority - it is also supported by SNP, Liberal Democrat and Plaid Cymru MPs;

*Amendment E, from Labour, which notes that Parliament has "decisively" rejected both Theresa May's deal and a no-deal and calls for a delay to Brexit "to provide parliamentary time for this House to find a majority for a different approach" and

*Amendment J, tabled by Labour’s Chris Bryant's to stop a third meaningful vote on the PM's deal.

Mark Francois, the Deputy Chairman of the ERG bloc of Eurosceptic Tories, pointed out Amendment B to reject a second EU referendum had been signed by "127 members of this house including the entirety of the DUP, 13 members of the Labour Party, and one independent to boot" as well as more than 100 Conservatives.

“It, therefore, had far more signatories than any other amendment on the order paper", declared the backbencher, adding that although he accepted the final decision on amendments was for the Speaker, he asked Mr Bercow why it had not been chosen while the rival amendment, Dr Wollaston’s, pursuing a second referendum, had been.

The Speaker hit back, telling MPs: “Members do have to take the rough with the smooth."

He explained while it was true the number of signatories was important, this was "not the only factor" to be considered and he stressed how he tried to "always do my best to be fair to the miscellany of different points of view represented in this House".

However, senior Conservative backbencher Sir Bernard Jenkin, raising a Point of Order, said there might be "some concern" over the selection of amendments around a second Brexit referendum, asking Mr Bercow what were MPs to conclude about "your views on these matters".

The Speaker replied MPs were "not to conclude anything" in respect of his views.

In this evening's vote, Conservative MPs have again been granted a free vote but it remains unclear whether they will be whipped to oppose amendments designed to pave the way for a second referendum or block a so-called People's Vote.

Earlier, Philip Hammond made clear it was "certain" MPs would vote this evening to authorise Mrs May to seek a delay to Brexit.

The Chancellor denied being at odds with the PM after he called for Parliament to seek a "consensus" solution to Brexit and to "explore other options" if her deal were voted down for a third time next week.

But Labour called on him to join them in cross-party talks on finding a "compromise" which could command the support of the UK Parliament after Mrs May's authority was severely dented by three defeats in the space of 24 hours.

Mr Hammond is the most prominent of a group of Cabinet ministers suspected by Leave-backing Tories of being prepared to accept a "softer" form of Brexit.