Peter Housden, the man strongly tipped to be the next head of the Department for Education and Skills, is to join another government department.
The director general of schools will become permanent secretary at the Office of the Deputy Prime Minister next month.
Mr Housden, a former teacher and chief education officer, was seen as a strong candidate to become the top civil servant at the DfES after David Normington, the present permanent secretary, was linked with a move to rejoin Charles Clarke at the Home Office.
A DfES spokeswoman said an announcement about Mr Housden's successor would be made in due course.
Documents released under the Freedom of Information Act show that the DfES has yet to make any civil servants redundant, despite a commitment to cut staff by a third by 2008.
Meanwhile, rumours of a ministerial reshuffle continue to circulate around Westminster and Whitehall. Suggestions that Ruth Kelly, the Education Secretary, could be moved were strengthened by the news that David Miliband, former schools minister, has appointed Janet Coull, a former DfES press officer, as his special adviser.
Mr Miliband, who is known to be disappointed not to have been made Education Secretary last year, has been tipped for a return to the department.
Reports suggest that Prime Minister Tony Blair is likely to reshuffle his ministerial team before the end of the year.