Theresa May has brushed aside warnings about the civil service's ability to take Britain out of the European Union while delivering the rest of the government's policy agenda.
Since the Brexit vote in June, a number of senior figures have warned that ministers may need to trim back their policy promises and provide extra resources if an already-stretched Whitehall is to take on the extra burdens of an EU exit.
Former head of the civil service Lord Kerslake told CSW that he believed there should be an end to some staff cuts, while Amyas Morse, the head of the National Audit Office spending watchdog, has warned that the civil service is being "set up to fail" because it is now overloaded with commitments.
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Similarly, the former head of the Foreign Office Sir Simon Fraser, along with MPs on the Foreign Affairs Committee, have called for an injection of resources at the FCO to help it build extra capacity, while Lord O'Donnell, the former cabinet secretary told The House magazine last month that the government would either have to "put a lot of resources into delivering Brexit – or stop doing some of the things they are doing at the minute".
But it was the findings of a fresh report by the respected Institute for Government think tank that prompted May to dismiss such concerns on Tuesday. The think tank's researchers, citing interviews with officials, called on ministers to ensure that departments had "sufficient staffing and money for both Brexit and existing commitments, or acknowledge that plans must be trimmed".
Appearing before the House of Commons cross-party Liaison committee, May was pressed on the IfG's report by Tory MP Bernard Jenkin.
"The Institute for Government has produced a paper which suggests that departments are having to choose between meeting the pre-existing commitments and demands that were placed on them before Brexit arose and the Brexit priorities," he told the prime minister.
"How confident are you that there is sufficient capacity across departments to deal with all these priorities?"
Responding, May said: "I'm afraid I'm tempted to say in answer to your question, Mr Jenkin, that I'm not at all surprised when former civil servants suggest we need to employ more civil servants."
That answer immediately provoked an angry response from one former official who is now a senior IfG fellow. Ian Magee, who served as second permanent secretary at the Department for Constitutional Affairs and as head of profession for the civil service's Operational Delivery Profession, said on Twitter that May had given a "disgraceful and ill-informed reply".
Meanwhile, Robin Munro, who is leading the IfG's Brexit work, pointed out that neither she or her colleague Joseph Owen had ever been civil servants, adding: "We just report what we found."
Elsewhere in the Liason Committee session, May would not give a guarantee that MPs will have a vote on the government's final Brexit deal, saying only that parliament would be able to "consider" and "discuss" the result of negotiations between the UK and Brussels.
"It is my intention that parliament should have every opportunity to discuss [these matters]," she said. "But I’m clear we deliver on the vote of the people.”