UK Government: All versions of Brexit will make us poorer
The new official figures come as Theresa May visits Scotland in a bid to sell her deal.
All scenarios of Brexit will make the UK poorer, according to new analysis by the UK Government.
Withdrawal from the EU under the proposed deal could cut Britain's GDP by up to 3.9% over the next 15 years, according to official figures.
If the UK was crash out of the European Union with no deal, it could deliver a 9.3% hit to economic growth over the same period.
The analysis concluded the UK would be poorer in economic terms under any version of Brexit compared with staying in the EU.
Even were Theresa May to pass her deal and then secure everything she wants in future trade negotiations, it would still represent a 2.5% hit to GDP, the study suggests.
The document also modelled the potential impact of these scenarios Scotland's economy, finding similar figures to the UK estimates, with a 2% cost to Scottish growth in May's best-case scenario and an 8% hit predicted if there is no deal.
It comes as the Prime Minister visits Scotland later on Wednesday in a bid to sell the agreement her negotiators struck with Europe this month.
The crucial "meaningful vote" on her plan in the House of Commons will take place on December 11 after five days of debate.
The 83-page analysis was drawn up by officials from Whitehall departments including the Treasury, the Department for Exiting the EU, Industry, Environment, International Trade and the Home Office.
The document does not attempt an exact forecast on the impact of May's deal, but compares it with the alternative scenarios of Norway-style membership of the European Economic Area (EEA), a Canada-style free trade agreement with the EU and a no-deal Brexit.
It finds that GDP in all cases will be reduced if migration from Europe falls from its current levels.
Potential outcomes range from a 0.6% reduction if the final deal involves frictionless trade and unchanged migration levels to 9.3% if a no-deal Brexit reduces net immigration by EU workers to zero.
National income would be an estimated 1.4% lower with EEA membership and 4.9% with a Canada-style deal if migration levels remained the same, the analysis indicates.
Were net migration to be cut to zero under a Canada-style deal, the hit to growth would be around 6.7%.
Chancellor Philip Hammond acknowledged that all possible Brexit options will make Britain worse off "purely in an economic sense".
He told the BBC the outcome of the Prime Minister's preferred Brexit plan will be a "slightly smaller" economy over the next 15 years.
But he insisted her plan will "minimise" the economic damage by reducing the barriers to trade that would arise with a hard or no-deal Brexit.
The SNP's Westminster leader Ian Blackford challenged May on the analysis at Prime Minister's Questions prior to her departure for Scotland.
He said: "Quite clearly, under any scenario, leaving the single market and the customs union we'll be poorer.
"The Prime Minister wants to take us back to the days of Thatcher and a belief that unemployment is a price worth paying, that's the reality.
"No government should choose to weaken its economy and make its citizens poorer, that's what the Prime Minister is doing."
Blackford added: "People in Scotland voted overwhelming to Remain, we voted for our rights to be respected and we are not prepared to give up those rights.
"The Prime Minister must explain to the people of Scotland why her deal will rob them of their rights as EU citizens."
May replied: "What the analysis shows is that this is a strong economy that will continue to grow and that the model which actually delivers best on delivering for the vote of the British people and for our jobs and our economy is the model that the Government has put forward."
She added: "He talks about what the people of Scotland voted for, they voted to stay in the United Kingdom and they voted for 13 Conservative MPs."
The UK Government paper comes only a day after the Scottish Government published its own study of the Brexit deal.
The analysis suggests the Prime Minister's proposed agreement could cost the equivalent of £1600 for each person in Scotland by 2030 compared to remaining in the EU.