Prospect Deputy General Secretary Dai Hudd said: “It is galling that despite detailed talks over the last eleven months, the Cabinet Office and Ministers have seen fit to press ahead with fundamental changes to the Civil Service Compensation Scheme without any meaningful attempt to reach agreement.

“The way this has been handled has caused considerable anger among our members who will meet next week to explore the options to challenge the government’s approach through the courts.

“Today’s announcement is all the more disappointing as we firmly believe that an alternative solution, which would have satisfied both sides’ objectives, was achievable. We will be writing to the Minister today requesting an urgent meeting before any amendments are laid in Parliament.”

Nevertheless, said Hudd, members had taken some comfort from the fact that union pressure had resulted in changes to the draft proposals that would afford extra protection for the lowest paid and those closest to retirement.

Prospect represents 34,000 specialist staff in the civil service.