London (CNN Business) It's official: The British government's plan for leaving the European Union will be bad for the economy.

The government published a report Wednesday that outlines the economic costs associated with a range of Brexit scenarios. The Bank of England followed later in the day with its own assessment.

The United Kingdom would be worse off under all scenarios studied by the government. Officials did not estimate the precise impact of the deal Prime Minister Theresa May has negotiated with the European Union , but even in the best case it too will mean a weaker economy than remaining in the bloc.

"It is true that the economy will be very slightly smaller, but if we do the deal in the way that the prime minister has set out and negotiated, that impact will be entirely manageable," UK Treasury chief Philip Hammond told the BBC.

The official estimates underscore the harsh economic reality of Brexit: Under any scenario, leaving the European Union will make Britain poorer than staying in.

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