Image caption Nicola Sturgeon said the Commons defeat was a "severe blow" to Mr Johnson

MPs putting Boris Johnson's Brexit deal on hold is a "severe blow" to the prime minister, Nicola Sturgeon has said.

The Scottish first minister reacted after MPs voted to withhold backing for the agreement negotiated with EU chiefs until exit legislation is passed.

The UK government will now put forward such a bill on Monday, with a view to a decisive vote on it on Tuesday.

Ms Sturgeon said the vote was a "severe blow" to Mr Johnson's "plan to bludgeon his bad deal through" the Commons.

Mr Johnson said he was "not daunted or dismayed" by the result, and said he still intended for the UK to leave under the terms of his deal on October 31.

However, he is compelled to ask the EU for an extension later today under the terms of legislation previously passed by opposition MPs.

The Commons held a Saturday sitting for the first time in 37 years to consider the exit deal agreed with European leaders earlier in the week.

MPs did not ultimately vote on the deal itself, after they backed a cross-party amendment from former Tory MP Oliver Letwin by 322 votes to 306.

The effect of the amendment is to withhold approval of the deal until legislation to enact it is passed, to prevent the UK from leaving the EU without a deal if there were any delay to the legislation.

The government has now moved to table a withdrawal agreement bill, with Mr Johnson telling MPs: "Next week the government will introduce the legislation needed for us to leave the EU with our new deal on October 31, and I hope that our EU colleagues and friends will not be attracted by delay - I don't think they will be."

Media playback is unsupported on your device Media caption Boris Johnson: "For the people of Scotland, they now have the chance.... to take back control of their fisheries."

Opposition parties are likely to seek to amend the legislation as it goes through the Commons, to include provisions such as a confirmatory referendum.

Ms Sturgeon said the delay meant the deal could be "subjected to real scrutiny", posting on Twitter: "PM sounding deflated and defeated - he knows this is a severe blow to his plan to bludgeon his bad deal through."

Mr Johnson needed 320 votes to get his agreement through the Commons, but was facing an uphill battle after losing the support of the DUP.

While he was backed in the Letwin vote by the 13 Scottish Conservative MPs, the amendment was passed with the backing of the bulk of Labour's members, including seven from Scottish seats, the 35 SNP MPs, and the four Lib Dems from north of the border.

The prime minister now faces the prospect of having to write to European leaders requesting a fresh extension to the Brexit deadline, under the terms of the "Benn Act" passed by MPs in September.

Mr Johnson was warned that he could end up in a Scottish court on Monday if he refuses to send the letter.

Court of Session judges said they could meet to examine the question of whether to use the court's powers to effectively sign the letter on Mr Johnson's behalf.

Media playback is unsupported on your device Media caption Ian Blackford: "Scotland has been totally and utterly shafted by this prime minister and this Tory government."

There were clashes in the Commons before the debate proper even began, with the SNP's Westminster leader Ian Blackford branding Mr Johnson's effort "even worse than Theresa May's deal", which was rejected by MPs on three occasions.

He said the prime minister "didn't even consider giving Scotland a fair deal".

Mr Blackford added: "This is a deal that would see Scotland shafted by this UK government, left at an economic disadvantage, with Scotland's views and interests totally disregarded by this prime minister and his government.

"He and his cronies in Number 10 don't care about Scotland - this Tory government has sold Scotland out and once again let Scotland down."

Mr Johnson replied that he had sealed "a great deal" for Scotland, England, Wales and Northern Ireland.

Final deal on offer

He said: "For the people of Scotland, they now have the chance, championed by wonderful Scottish Conservative MPs, to take back control of their fisheries from the end of next year and allow the people of Scotland at last to enjoy the benefits of their spectacular marine wealth - in a way they would be denied under the SNP, who would hand back control of Scottish fishing to Brussels."

The latest proposal removes the much-disputed "backstop" proposals for the Irish border post-Brexit, and would instead see Northern Ireland remain in the UK's customs territory - while adhering to a limited set of EU rules on goods. Representatives in Northern Ireland would be able to decide whether to continue this arrangement every four years.

European Commission President Jean-Claude Juncker said it was a "fair and balanced agreement" - and suggested that it was the final deal on offer, saying there would be "no other prolongation".

Ms Sturgeon has rejected this, saying: "The alternative to this deal is the Benn Act, which would require an extension request. That's the law of the land. So anybody who says that it's a choice between this deal and no deal is frankly not being straight with people."