Labour will seek to push through moves for a second EU referendum this week in the Commons, it has been confirmed.
Shadow Brexit secretary Keir Starmer said that an amendment will be tabled to Boris Johnson's EU Withdrawal Bill when it comes before MPs this week. The move will have the backing of the SNP and Liberal Democrats, but will need other MPs to switch to secure a majority.
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The UK Government will press ahead with its Withdrawal Bill this week, despite pulling a "meaningful vote" in the Commons yesterday after being defeated on the "Letwin amendment" which would block a No Deal scenario. Ministers still believe they have the support which could see legislation passed, meaning the UK could still leave the EU on October 31 as scheduled.
Boris Johnson has sent an unsigned letter to EU leaders seeking an extension if no withdrawal agreement is secured by the end of the month.
Sir Keir said the opposition is now poised to step up moves for a second vote.
"Whatever deal gets through, it should be subject to a referendum," he told the BBC's Andrew Marr show today.
"We have already voted, I think, three times as a party for a second referendum with a three-line whip behind it.
"What we are trying to achieve is, this deal in particular but any deal, is put up against remain in a referendum.
"The position we have adopted is whatever the outcome, whether it's Boris Johnson's bad deal or a better one which could be secured, it has got to go to a referendum up against remain."
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The scenario would see Labour sign up the Withdrawal Bill allowing it to pass - provided it went back to the people in the form of a confirmatory People's Vote.
And SNP Westminster leader Ian Blackford confirmed today that Labour would support this.
"Yes, well that's been our position for a very considerable period of time. Of course we would support that."
But he warned that there would been to be a "Government in place" which could do that, meaning a general election would be required first.
Government ministers still believe that they can secure the switch of about 8-9 MPs from Saturdays defeat which would allow the Withdrawal Act to pass, allowing Brexit to happen on October 31.
Chancellor of the Duchy of Lancaster Michael Gove told Sky News's Sophy Ridge On Sunday: "We are going to leave by October 31st. We have the means and the ability to do so and people who - yesterday we had some people who voted for delay, voted explicitly to try to frustrate this process and to drag it out.
"I think actually the mood in the country is clear and the Prime Minister's determination is absolute and I am with him in this, we must leave by October 31st."
Mr Johnson had been legally required to send the letter and stressed to Brussels he was only sending it at Parliament's bidding.