Theresa May and Jeremy Corbyn clashed at Prime Minister's Questions just minutes after the government published its economic analysis of the proposed Brexit deal.
The forecasts suggested the UK economy would be 3.9 per cent smaller under Ms May's plan than it would if the country remained in the EU.
However, the prime minister denied her plan would make Britain poorer, insisting the economic analysis "does not show that we will be poorer than the status quo".
Later in the day, separate analysis from the Bank of England said the pound would crash, inflation would soar and interest rates would have to rise if Britain crashes out of the EU without a deal.
A disorderly Brexit could see the economy shrink by more than 10 per cent compared to current trends, it said.
Ms May has embarked on a two-week campaign to persuade the country to back her plan, before it is put to the Commons on 11 December.
But she faced a fresh row after ministers confirmed they were planning to ignore a Commons vote demanding they publish the full legal advice they have receive on Brexit. Instead, only a summary will be released.
John Bercow, the Commons Speaker, said he was willing to consider whether a contempt of Parliament had been committed and encouraged Sir Keir Starmer, Labour's shadow Brexit secretary, to write to him about the matter.
As it happened...

Britain will be poorer if MPs back Theresa May’s Brexit deal, Philip Hammond admits
There will be a cost to leaving the European Union because there will be impediments to our trade'He said:
"I'm the chancellor so of course I look at the economy as being of overriding importance, but there are other considerations.
"And I recognise that many people feel very strongly about the need to leave the European Union to regain control of our fishing waters, to regain control of migration and control of our borders, to have the right to do third-country trade deals.
"These are things which have value to people, and it is true that the economy will be very slightly smaller if we do the deal the way the prime minister has set out and negotiated, but the impact will be entirely manageable."
"There's a very important principle here, that the government must be able to commission impartial legal advice which absolutely tells it like it is to enable it to shape its decisions, while always complying with its legal obligation in the negotiations."It would be impossible for government to function if we create a precedent that the legal advice that the government receives has to be made public.
"We must have, as every other citizen has, the right to take privileged legal advice which remains private between the lawyer and the client.
"So the client has the ability to ask the difficult questions, to receive full and frank legal advice, and then to make a decision based on that full and frank advice."

Unpaid carers will be asked to repay up to £50,000 in benefit overpayments, government says
Senior MP condemns ministers' 'ineptitude' after revelation that people have wrongly received tens of thousands of poundsMr Gove told the environment committee: “It is the case that our SI preparation was “at red”... but it is now "amber/green" after the hard work of officials.”
The comments came in the Brexiteer minister's first appearance before MPs since he opted to stay in the cabinet and fight for Ms May's deal, rather than resigning.
“Please don’t think that what you are doing and the extension of the transition period won’t affect the very industry you are trying to save because it will.
“I’m very angry. Sea bass is a very high-value fish. Basically those vessels are throwing away almost £10,000 pounds back into the sea now because they have no quota.
“Mr Macron’s [French president Emmanuel Macron] fishing fleet are allowed to go and catch it and take it back to France free of charge and basically land it. The UK exchequer is being denied income.”

Government 'complacency' means there is 'real prospect' of border chaos in case of no-deal Brexit, MPs warn
Key Commons committee also criticises minsters' use of 'gagging clauses' to silence business groups over BrexitThe environment secretary said it was true that the water industry is reliant on chemicals from the EU but the overwhelming majority enter the UK through ports other than Dover, such as Immingham, in Lincolnshire, so less likely to be caught in a backlog.
The environment secretary admitted there was "a potential danger” but said action had been taken to make sure that does not arise.
He insisted water is “completely safe to drink” and denied being the source of the story in the Mail on Sunday.
However Tory MP Dr Caroline Johnson told him he needed to reassure the public to prevent people from stockpiling bottles of water.
Mr Gove said he didn't want to be caught up in Project Fear, but he wanted to be honest on the impact of no-deal on areas such as farming.

UK to be worse off and wages to fall under every scenario if it leaves EU, government analysis finds
Theresa May's Brexit plan will deliver a 3.9 per cent hit to GDP and workers’ wages will fall, according to the best estimate of government officials.Please allow a moment for the live blog to load
The Independent has launched its #FinalSay campaign to demand that voters are given a voice on the final Brexit deal.
Sign our petition here