Brexit preparations risk becoming a "damaging and unmanageable muddle" unless the Government steps up its efforts to get ready for leaving the EU, an influential Commons committee has warned.
The Public Accounts Committee (PAC) said Whitehall departments have been "too slow" to face up to the realities of leaving the European Union, and "lack a credible plan" on how to cope with more than 300 Brexit-related projects.
Urgent action is needed to recruit staff, streamline decision-making and reduce other commitments, MPs warned, adding: "The real world will not wait for the Government to get its house in order."
It comes as Theresa May geared up for two days of tense meetings with her Brexit "war Cabinet" where senior ministers will thrash out the UK's position on its future relationship with Europe.
With 14 months to go until exit day, the committee said David Davis' Brexit department needed to take the lead by coming up with a "credible" plan to recruit skilled civil servants needed to deliver Brexit and to prevent decisions being mired in "potentially unwieldy and overly-complicated" bureaucracy.
The cross-party MPs demanded "greater transparency" on the costs of delivering Brexit and what progress had been made, as they found the lack of information was "undermining" Parliament's attempts to scrutinise the process.
Eurosceptic Tory Sir Geoffrey Clifton-Brown, the committee's deputy chairman, said: “The Government has identified over 300 work streams to complete as a consequence of the UK’s departure from the EU – a byzantinely complicated task with the potential to become a damaging and unmanageable muddle.
“It is concerning that Government departments still have so far to go to put their plans into practice.
“DExEU and the Cabinet Office accept the pace of work must accelerate, a point underlined by DExEU’s senior civil servant when he told us that there needs to be a ‘sharp focus on the world of the real’.
“That real world will not wait for the Government to get its house in order.”
Civil servants will also have to cope with delivering more than 1,000 new laws before Britain leaves the bloc, prompting warnings from Brexit officials that there will be "minimal room" for any other domestic matters.
Labour MP Ian Murray, a supporter of the Open Britain campaign for a soft Brexit, said the report laid bare how the EU divorce will be a "monumental distraction" from domestic policy for years to come.
He said: "Once again, today we have evidence of how completely unprepared the Government are for delivering it.
“The Prime Minister launched the Article 50 process almost a year ago and yet she and her Cabinet still haven’t discussed, let alone agreed, what they want from the negotiations. The fact is, Brexit on the terms it was promised during the referendum is not deliverable.
“Given the mess the Government is making of the negotiations, it would make much more sense to extend the Article 50 process than to continue stumbling around in the dark.
A Government spokesperson said: "The Government is committed to ensuring that the right skills and resources are available across all departments to deliver a successful Brexit.
"We have built two new departments, the Department for Exiting the EU and the Department for International Trade, to help deliver a smooth and orderly exit from the European Union and forge new bold and ambitious trade agreements across the world.
"And we have repeatedly set out that we are determined to continue recruiting the brightest and the best talent from the public and private sectors and the capability of all departments is regularly reviewed.
"This was made clear by Philip Rycroft, Permanent Secretary at DExEU, who told the Committee that resourcing in his department is kept under constant review, and that is not just about numbers; it is also about the sorts of people recruited by the Department. And we will continue to adapt as need arises.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies