Chancellor Philip Hammond took more than two years to prepare the port of Dover for a no-deal Brexit.
He told the Finance Committee: "The essential things that need to be done in Dover if we want to have a WTO agreement with the European Union would involve some significant infrastructure work that could not be done in months. It would take years to finish. "
When asked if it would take two years, he said, "Well, I would suggest that the planning system might have difficulty approving such significant infrastructure changes in two years, let alone building them. I think it would take much longer to complete the major infrastructure changes that would be needed if we were to consider a long-term WTO-like relationship. "
The chancellor also revealed that he wants to hold a spring declaration before the end of March.
Britain will leave the EU on 29th March.
He told MEPs that the modeling by the Treasury Department and other Whitehall departments had shown Britain would be economically worse off under any Brexit scenario.
However, Mr Hammond insisted that it would be worth taking a "very small" economic blow under the government's preferred Brexit to prevent the EU's withdrawal from being politically and socially damaged.
The Chancellor told the Commons Treasury Committee: "The analysis clearly shows that leaving the EU in any scenario we model costs money – economic costs."
He added, "In my opinion, we need a way to heal our country, we are a deeply shattered country with a strongly polarized view and confidence in the political system that has been damaged accordingly, I would suggest … that split Countries are not successful countries.
"I have thought long and hard about it, and I have come to the conclusion that the future success of our country depends on the fact that we are implementing the referendum instructions of the British people and leaving the EU, but in a way that does not Minimum reduces the impact on our economy and maximizes the opportunities we have in the future, so that we as a nation can come together and work together to seize these opportunities in the future.
"Any solution that the country has shared has, in my opinion, negatively affected a large part of the population that feels betrayed, which would have negative political and societal implications, the very low economic impact of the White Paper scenario. far outweighed. "