NHS England has asked hospitals to provide around 95% of all planned operations and procedures. How this is done is down to each hospital to decide.

The BMA acknowledges in its letter that, ‘as clinicians and leaders, you know what is safe in your trust' and advises, ‘where necessary, you should appropriately incentivise these [non-striking] doctors to take on this additional extra-contractual work. Where required, you should reschedule less urgent activity to prioritise the safety of emergency care.'

The BMA's chair of council, Dr Tom Dolphin, said: ‘The purpose of the letter to trust chief executives is to make clear our aim that while resident doctors are taking lawful industrial action, patients will remain safe.

‘As the head of NHS England, Jim Mackey has set a very ambitious target for hospitals to effectively carry out almost as many operations as they would on non-strike days. Whilst we know that some surgery is routinely cancelled for a variety of reasons every day anyway, trying to run a near normal elective service on a strike day alongside urgent and emergency care will be challenging.

‘We have been clear in our letter that resident doctors have a legal right to take strike action and must not be bullied or coerced into staying in work. When and where there are legitimate reasons for calling them back in – such as a mass casualty event - they will be asked to do so. However, what we do not want to see are requests for doctors to leave the picket line because a trust has failed to properly plan the extra cover needed to meet this government target or has not offered suitable incentives for non-striking doctors to cover shifts.'

In addition, the letter makes clear that a request for a resident doctor to return to work for a limited period to maintain safe patient care – known as a ‘derogation,' is not ‘in place to avoid disruption caused by industrial action but to ensure that in unexpected and extreme circumstances patients will continue to receive safe care.'