The Government said it was "disappointing" that the PCS union is planning three months of industrial action, including a huge strike on Budget day.
A Cabinet Office spokesman said: "It is disappointing that, yet again, the PCS insist on pushing for futile action which benefits no-one, and damages the services they deliver to the public."
More top news
Six teenagers had a lucky escape after almost getting cut off by the sea while searching for Pokemon Go characters.
Clinton needs to win over doubters all over the USA. We joined a family of sceptical and divided voters to see if her message hit home.
An ultra marathon runner found the perfect running mate as he competed in the 4 Desert race in the unlikely form of a stray dog.