The one-day strike action will be held on Thursday, with both GPs and hospital doctors involved.

UK Health Secretary Andrew Lansley has claimed that up to 1.25m GP appointments will be delayed for days or even weeks, while up to 30,000 operations and 200,000 hospital outpatient appointments could be rescheduled.

He wrote to the British Medical Association on Tuesday with a final offer of a £68,000-a-year pension, urging the union to re-think the plans to strike.

"We deeply regret the disruption this will cause for patients - though we are adamant that patient safety will not be affected," a BMA spokesperson said.

It's understood doctors will see anyone who is ill on Thursday, but will not complete any paperwork - people have been advised to only use services if there is an urgent need.

Northern Ireland's largest public sector trade union, NIPSA, has expressed support for those taking strike action.

General Secretary Brian Campfield said it was a sign of how "out of touch" the government was with society.

"The action - by a highly-regarded group of public sector workers, who are at the heart of the community - should encourage everyone who is suffering from the government's vicious austerity programme to take an active part in the campaigns to stop the cuts and to prevent any further harm being done to working people, their families and communities," he said.

"This action will also let the millionaire cabinet know that the opposition to their austerity policies is intensifying."