The prospect of a second referendum on Brexit linked to any deal struck with Brussels is fading fast after Jeremy Corbyn and Nicola Sturgeon both played down the proposal today.
The First Minister questioned whether such a move was "deliverable" while Mr Corbyn warned his MPs against agreeing to such a deal. Both leaders want an election to take place first.
Hopes of a Brexit deal being struck between the UK Government and Brussels have been revived after intensified talks got underway last week.
But any agreement would still have to be passed in the Commons and speculation has been mounting that tying the deal to a "confirmatory" referendum could secure its passage. Labour's Brexit spokesman Keir Starmer suggested this could be the way ahead in a weekend interview.
Read more: Cross-party Brexit deal needs to include second referendum, says Sir Keith Starmer
But a fresh vote appears to have nosedived after it met with a frosty reception from the leaders of the two main opposition parties today.
Mr Corbyn signalled Labour was unlikely to back any Brexit deal brought back by Mr Johnson, even if there was a confirmatory referendum.
"I think many in Parliament, not necessarily Labour MPs, others, might be more inclined to support it (if there was a referendum) even if they don't really agree with the deal. I would caution them on this," he said.
Mr Corbyn insisted that if the Government fell, he should have the first chance of forming a new government rather than a more consensual figure who could command cross-party support.
"I am the Leader of the Opposition. All the British parliamentary precedents going back as long as you care to look are that the first option is that the leader of the opposition is invited to form an administration in order to deal with the specific points to make sure that we get a deal with the European Union," he said.
"We will form an administration if this Government collapses with the purpose of a deal and take this country forward to decide its own future through an election and the people get to decide their future in a referendum."
Mr Corbyn has pledged that an incoming Labour administration would go on to stage a referendum on Brexit - after securing a fresh deal with the EU.
Read more: Jeremy Corbyn: Labour would 'immediately legislate' to hold second Brexit referendum after election win
SNP policy is to back a second referendum, but Ms Sturgeon today raised concerns today about what is "deliverable."
She added: "I'm still of the view that the better sequence of events in principle, and for practical reasons, is for the opposition to try to get rid of Boris Johnson in a vote of confidence, to have the extension assured and then have a general election."
The SNP leader said she would not "close down options" and may back a referendum.
"One of the practical issues I think about having a referendum before a general election is we've seen how difficult it's been - thus far impossible - for the opposition to come together, to unite behind a leader of an interim Government that might be in office to secure and extension.
"If there is to be a Government that legislates for a referendum then it has to be in office for a reasonable period of time. Then it has to do other things, it has to govern, it might have to put through a budget. I question whether it would be possible for the opposition to come together which is why I think an election, where parties can seek a mandate for a second referendum, is the better option."
Ms Sturgeon made it clear that the SNP would not back any deal which would be secured by Mr Johnson, insisting it would have a damaging impact on "environmental rights, consumer rights and workers rights.
"We would be looking a race to the bottom where priorities would be trying to get trade deals with the likes of Donald Trump - that's not acceptable to the SNP."