Ambulance crews across Sussex could take industrial action over pay and conditions within weeks.

Members of trade union Unison voted four to one in favour of the action in a move which could threaten the safety of patients.

Although details of the action have not been decided, it is likely crews will refuse to work overtime or give up their rest days to cover for absent colleagues.

The changes could be implemented within two weeks.

Unison Sussex branch secretary Colin Rhodes said: "Our members have given us a clear and positive mandate to take industrial action.

"Action which frustrates the employer may, as a consequence, affect our services to the public. We do not want to endanger public safety but, with all our good intent, we cannot guarantee that nobody will be affected by this."

Of the 386 Unison members balloted, 80.8 per cent, voted in favour of action short of a strike, with 19.2 per cent against.

The Association of Professional Ambulance Personnel (APAP), which has more than 100 members, was also balloted, with 63.8 per cent voting in favour of action.

Employees are asking for a five per cent pay increase, rather than the 3.6 per cent they have been offered by Sussex Ambulance Service NHS Trust.

The average ambulance worker earns £20,000 a year and a five per cent pay rise would increase their wage to £21,000.

Unions also want a decrease in the working week, from 42 hours to 40 and an increase in leave. In addition, they are calling for cost-of-living supplements, similar to those nurses are awarded and the option for early retirement at 55.

The trust has offered some employees a three per cent rise in exchange for an extra day of leave.