Non-urgent operations and outpatient appointments could be cancelled tomorrow as a result of industrial action by the British Medical Association.

NHS Outer North East London, which looks after Barking and Dagenham GP practices, said surgeries are unlikely to be significantly affected but added that action by hospital doctors could means “non-urgent care, such as outpatient clinics and some planned operations and tests will be affected”.

The walk out, which is due to a dispute over pensions, will be the first by doctors in 40 years.

ONEL said in a statement it wants to “reassure the public that all of our GP practices will be open and anybody needing urgent treatment on Thursday will be able to get it”.

A spokesman added that all practices in the borough will be open and those who have booked appointments should see them go ahead but those wanting to book may have to wait until Friday.

The statement went on: “We do not expect much disruption at family doctors.

“Hospital doctors taking action will make sure all patients with urgent care needs have those needs met. Inpatient treatment, urgent care, and cancer care will not be affected. Only work that can safely be postponed without patient harm will be.

“Unfortunately, we cannot rule out delays for non-urgent patients and we may need to reschedule some patients at short notice.”

The hospital trust, which looks after King George and Queen’s, has contacted people whose operations or appointments are cancelled.

Meanwhile, non-medical staff employed by the BMA are striking today in a separate dispute over pensions.

The BMA staff, who are represented by the GMB union, are taking to the picket lines in central London over a 1.5 per cent pay offer they deem unacceptable.

Tony Warr, GMB organiser, said: “As the BMA prepares for the first industrial action by doctors in 40 years they should enter into talks to avert industrial action by its own staff.”

BMA chief executive Tony Bourne said the pay offer was a “fair one given the challenging economic environment facing all employers”.

Anyone in doubt of the treatment available call NHS Direct on 0845 46 47.