The Department for Business, Innovation and Skills is considering plans to reduce its workforce by more than 4,000, according a leaked internal document.
Ahead of November's Spending Review, BIS commissioned consultants from McKinsey to help it draw up a strategy – called "BIS 2020" – to cut costs in the department and its partner agencies.
The Treasury ultimately asked BIS to make savings of £100m to its administrative spending by 2019-20, and eyed £150m-worth of cuts to the department's programme spend.
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But the department has opted to go further still, with its Single Departmental Plan published earlier this year saying it would save £350m over the course of the parliament.
A BIS briefing – seen by CSW and which appears to have been drawn up ahead of the March Budget's announcement of a further government-wide departmental efficiency review – makes clear that the £350m includes £100m of savings that go beyond the control totals agreed by the Treasury.
And it details the scale of job cuts that the department would need to make if it were to implement the full McKinsey proposals.
According to the document, BIS will need to cut 1,526 posts by 2020 under current spending projections. But the briefing shows that that the department would need to cut a further 2,577 roles under the full BIS 2020 McKinsey proposals.
The McKinsey projections would, it shows, see over 1,500 staff cut from core BIS operations – some 750 more than the department's current plans – with around 900 jobs going at the Research Councils and almost 2,000 at the Student Loans Company, which currently has 2,500 staff.
A spokesperson for BIS said the department did not comment on leaks.
But they added: "To be clear, there have been no changes to the plans already announced and discussed extensively with parliament.
“We have a responsibility to the taxpayer to ensure as much of the department’s funding as possible is focused on front line services. We have deliberately set ourselves challenging savings targets consistent with the Spending Review and we will continue to explore options in detail before making decisions.”
Shadow cabinet office minister Louise Haigh – who has been highly critical of the department's decision to close its Sheffield policy operations by 2018 – meanwhile accused business secretary Sajid Javid of seeking to make "secret cuts" which "go further than even the chancellor thought possible".
“As his dedicated civil servants are working all hours to get to grips with the steel crisis, Sajid Javid is concocting a secret plan to lay them off,” she added.
The Public and Commercial Services (PCS) union staged a rally over the weekend to oppose the decision to shut the BIS Sheffield site and move the department's policy roles to its headquarters in London.
BIS permanent secretary Martin Donnelly has defended the BIS 2020 strategy, telling MPs earlier this year that it would involve "a great simplification in how we do things", including "focusing our expertise in specific areas" and improving BIS's use of digital technology.