Trade union Unite has recommended that ancillary and ambulance staff in the NHS reject the government's three-year pay offer.

A union committee representing 12,000 ancillary and ambulance employees has decided the offer of 2.75 per cent this year, 2.4 per cent in 2009-10 and 2.25 per cent in 2010-11 plus extra for lower paid workers does not contain enough flexibility to counter possible inflation rises.

Fellow union Unison, which represents more than 400,000 NHS employees, voted on Tuesday to allow its members a free choice on the deal.

Another Unite committee, which represents more than 100,000 health staff including health visitors, mental health nurses, sexual health advisers and members of the Medical Practitioners' Union, is set to consider the offer next week.

But in a letter dated 7 April seen by unions, NHS chief executive David Nicholson warned that if employees did not accept the offer, the government reserved the right to stage or cut it as part of a one-year settlement.