SCOTLAND’S politicians are “critical” in the fight for a second Brexit referendum, a former UK cabinet minister has said.

Labour peer Andrew Adonis will call on his party to “get off the fence” and back a so-called People’s Vote at an event in Edinburgh today, as he argues Scottish MPs will play a key part in shaping the future.

It comes as London mayor Sadiq Khan urged the EU to prepare to delay Brexit to allow time for a second referendum or a change of government.

Lord Adonis will speak at an event at Edinburgh University examining the impact of Brexit on young people, organised by the pro-EU advocacy group Our Future Our Choice.

He will insist Scotland’s MPs are “critical in the fight for a People’s Vote”.

He will add: “Scotland voted overwhelmingly to Remain, so the Scottish Labour Party must get off the fence and back a People's Vote.

“The vast majority of Labour Party supporters in Scotland want one, and they do not want their only pro-EU option to be the SNP.”

Nicola Sturgeon has insisted her MPs will back a new Brexit referendum if there is a Westminster vote, but Labour’s leadership has so far failed to endorse a fresh poll. Scottish Labour would not comment on Lord Adonis' latest remarks.

Meanwhile, Ian Murray, the pro-EU Labour MP for Edinburgh South, will use today’s event to call for Scottish Tory leader Ruth Davidson – who backed Remain – to throw her weight behind a second referendum.

He will say: “Tory leader Ruth Davidson backed Remain and it’s time she told her Scottish MPs to stop acting as Lobby fodder for the Brexiteers, and get behind a People’s Vote.

“She can’t claim to support the Union while putting it at risk with a hard Brexit. Her MPs have a key role when this comes to the Commons – it’s time to put the country before the Tory Party.”

Labour MEP Catherine Stihler will argue Brexit “threatens the opportunities for young people from across Scotland”.

She will say: “We must do everything we can to give people an opportunity to prevent Brexit, and there are tens of thousands of youngsters who didn’t get a vote in 2016 who back a People’s Vote. Future generations will not forgive us if we go ahead with Brexit.”

Mr Khan held talks with EU chief negotiator Michel Barnier in Brussels yesterday, insisting he wanted to avert a "political and economic crisis".

The Labour mayor said Mr Barnier had been “willing to listen” to concerns, adding: "I made the point that a bad Brexit deal, or even worse no deal whatsoever, it's bad for London, it's bad for our country but it is bad for the EU as well.

"He gets that. The point I'm sure he would make if he was here is that the ball is in the court of the British Prime Minister and it's important that we understand the consequences of the Article 50 notice being served when it was."

Liberal Democrat leader Sir Vince Cable, the SNP's Westminster leader Ian Blackford, Plaid Cymru Westminster leader Liz Saville Roberts and Green MEP Molly Scott Cato all held talks with Mr Barnier at his Brussels office on Thursday.

Downing Street later dismissed claims from Sir Vince that a chaotic Brexit could pose a risk to hit TV show Strictly Come Dancing, as many of the professional dancers come from EU countries.

Meanwhile, political leaders in Scotland and Wales have joined forced to argue a scheme to allow EU nationals to remain in the UK after Brexit should be extended to family members.

The EU Settlement Scheme pilot, due to begin in November, is open to health and social care workers and university staff, offering them the chance to apply for settled status before the UK leaves the bloc in March.

However family members are not included, and will have to wait until a later date to have their status confirmed.

Scotland's Health Secretary Jeane Freeman and her Welsh counterpart Vaughan Gething urged UK immigration minister Caroline Noakes to reconsider, and offered to host a pilot in which relatives can take part.

They insisted they would not “actively promote” the scheme unless this is done.