Mark Serwotka, general secretary of the largest civil service union, PCS, said Mr Maude should apologise.

BBC: Civil service unions deny deal with government

Lawyers acting for civil service union the PCS wrote to Michael Gove reminding him of his duty to follow agreed redundancy procedures.

BBC: DfE warned over potential unfair dismissals claims

The largest civil service union is to unveil the result of a national ballot that could lead to walkouts at the time of the Budget later this month.

BBC: PCS strike vote: Results of national ballot due