SCOTTISH Labour is coming under new pressure to back membership of the single market after a leaked analysis by the UK Government concluded Britain would be worse off, whatever deal is struck with Brussels.

Richard Leonard and his Brexit spokesman Neil Findlay say they want a “jobs first Brexit” but last night pro-EU parties said the study by Whitehall civil servants suggested this was impossible.

“It is ordinary families, workers and businesses across the country that will pay the price of a hard Brexit – we know in Scotland alone 80,000 jobs would be lost, and the Scottish economy would be hit to the tune of £12.7 [billion] a year, the equivalent of £2300 per year for every person in Scotland,” said SNP MSP Joan McAlpine.

READ MORE: LibDem peer slams UK for treatment of Scottish Government

“As we hurtle towards the EU exit door it is vital that we have a strong and effective opposition making the case for our single market membership. The Tories and UKIP might be the driving force behind a hard Brexit but Labour will be equally culpable for the lasting damage it causes if they continue to stand by and let the Tories have their way.”

Ross Greer MSP, the Scottish Greens’ Europe spokesperson, said: “It’s now clear as day, there is no such thing as a ‘jobs-first Brexit’ and it is plainly dishonest for any party to claim there is.

“The leaked analysis is alarming, but hardly surprising because we’ve known for a long time now that Brexit outside the single market will cost 80,000 jobs in Scotland and lower wages by an average of £2000.

“No political party can now seriously attempt to sugar-coat leaving the European Union by suggesting that it’ll be good for people’s livelihoods so the question for our colleagues has to be, why inflict this damage on Scotland when we voted overwhelmingly against it?”

Scottish Liberal Democrat leader Willie Rennie also appealed to Labour to review its position.

“It is time for Labour to come on board and protect the UK and Scottish economies,” he said.

“When so much is at stake, our country is badly served by Labour waffling and shuffling their way round Brexit and the Conservatives refusing to publish any economic forecasts at all. All the Holyrood parties should back the Liberal Democrat call for a referendum on the final Brexit deal.”

The leak of the economic impact analysis, which was drawn up for the Department for Exiting the EU, triggered renewed demands from opposition parties to release the full details.

The document, seen by the BuzzFeed News website, concluded economic growth would be lower under a range of potential scenarios. Even if the UK was able to negotiate a comprehensive free trade agreement, it estimates growth would be down five per cent over the next 15 years.

That would rise to eight per cent if Britain left without a deal and was forced to fall back on World Trade Organisation (WTO) rules. Alternatively, it concluded that even in the best scenario if the UK were to retain access to the single market through membership of the European Economic Area the loss would be two per cent.

UK Labour will today seek to force the Government to release its latest assessment of the impact of Brexit on the economy through a binding Commons vote.

In an opposition day debate, the party will use the same archaic parliamentary procedure it adopted last year to force ministers to release Brexit impact papers to a Commons select committee.

In the Commons yesterday, a number of pro-Remain Tories joined opposition MPs in calling for the analysis to be released, suggesting the vote could be close.

Former chancellor Kenneth Clarke accused ministers of trying to protect the Government from “political embarrassment” in refusing to release the document.

Tory MP Heidi Allen added: “This is a one-time deal only, and I for one owe it to my constituents to prove to them I have exercised full scrutiny.”

Theresa May has sought to play down the document, telling the meeting of the Cabinet that it represented “initial work” by officials which had not been signed off by ministers.