The plan would also involve keeping Northern Ireland in the single market to help maintain frictionless trade across the border with the Republic while mainland Britain would be outwith the single market.
"Trade from Great Britain into Northern Ireland would be in danger of restriction".
The OBR said weaker economic activity and higher prices could result from a no-deal Brexit.
Instead she proposed Britain as a whole stay temporarily aligned with the EU's customs union until a wider trade deal is agreed.
"The Johnsonian Canada plus plus is as big a pipe dream as Chequers", he said. That would allow for the United Kingdom and European Union to sign off the deal.
The Prime Minister relies on the support of 10 of Northern Ireland's DUP MPs to prop her up in the House of Commons and to secure their backing senior Tories are ready to offer them a bribe.
It comes as the deadline looms for a deal between London and Brussels.
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"Triggers of serious mental illness such as economics and social stresses are staring at us in our very youthful years". Stigma is part of the reason why mental health services are not well developed in many countries, the report said.
EU's chief negotiator Michel Barnier has said there could be a deal by next Wednesday but only on the condition the Prime Minister agrees to install a border between Northern Ireland and the rest of the UK.
It will follow another Whitehall meeting of the Joint Ministerial Committee, which will be attended by Mr Lidington and his colleagues Dominic Raab, the Brexit Secretary, and David Mundell, the Scottish Secretary. Can all three ever be satisfied with the terms of a Brexit deal?
Jacob Rees-Mogg, leader of the influential European Research Group of Brexiteer MPs, said: "It is worth remembering that income tax was introduced as a temporary measure".
The agreement will also see Northern Ireland remain within the single market in a bid to avoid a hard border on the island of Ireland, should both sides fail to secure a trade deal after the transition period.
His constituency contains the port of Larne, identified by European Union chief Brexit negotiator Michel Barnier as a place where checks on animals and animal products from Great Britain into Northern Ireland could be intensified in order to prevent a hard border with the Republic of Ireland.
He added: "Agreement is within reach if we have the negotiations on October 17 at the next council meeting".
At Westminster, Mrs May told MPs that it was "in the national interest" for MPs from all parties to back the deal she brought back from Brussels. "That is why we are interested in maximising an orderly withdrawal and minimising the cost of withdrawal".