A strike by resident doctors “enormously undermines the entire trade union movement”, Wes Streeting has argued, urging them not to join industrial action on Friday morning.

In an article for the Guardian, the health secretary says the decision by the British Medical Association (BMA) to push for new strikes in England immediately after receiving a pay rise of 22% to cover 2023-24 and 2024-25 is unreasonable and unprecedented.

Taking aim squarely at the leadership of the BMA, which represents the medics formerly known as junior doctors, Streeting condemns their demand for a fresh 29% rise over the next few years. He says that while there was 90% backing for the strike, it was on a turnout of just over 55% of members.

Streeting says the move to strike after the offer of a 5.4% pay rise for 2025-26, was rushed into and is “bitterly disappointing” amid efforts to improve NHS services.

“There was a deal here to be done,” he writes. “Instead, the BMA leadership’s decision to not even consider postponing these strikes will place an enormous burden on their colleagues, and hit the recovery we can all see our health service is making.

“Not only that, it enormously undermines the entire trade union movement. No trade union in British history has seen its members receive a such a steep pay rise only to immediately respond with strikes – even when a majority of their members didn’t even vote to strike. This action is unprecedented, and it is unreasonable.”

The BMA argues that resident doctors have seen their pay fall by a much greater amount in real terms since 2008-09 than the rest of the population. “Doctors are not worth less than they were 17 years ago, when austerity policies began driving wages down. We’re simply asking for that value to be restored,” it said.

Streeting says resident doctors have privately contacted him to express their dismay at the decision to strike, saying they “feel the BMA’s leaders are out of lockstep with not just patients but most resident doctors themselves”.

The health secretary urges doctors to defy their union and not join in the strike, which runs until 7am next Wednesday.

“I am urging resident doctors to not follow the BMA leadership, who I do not believe are representing the best interests of their members, any further down this path as strikes begin on Friday at 7am,” he writes.

The public have been urged to keep coming forward for NHS care during the strike, and NHS England has urged hospital chief executives to keep routine operations and appointments and only reschedule if there is a risk to patient safety.

A Department of Health and Social Care blog noted that the NHS was “taking a different approach” after learning lessons from previous strikes, and would avoid cancelling planned appointments for illnesses such as cancer because this posed “a risk to patients too”.

On Wednesday, the Academy of Medical Royal Colleges urged the BMA to suspend its guidance to resident doctors that they do not have to share their intentions to strike with their employers – as is their entitlement under employment law – to enable hospitals to better plan.

It is understood that in previous strikes, healthcare leaders filled rota gaps of unknown size by overstaffing and cancelling procedures, with the result that there was insufficient work for some highly paid consultants.

Fewer resident doctors are expected to go on strike on Friday than in the previous round of industrial action that started in 2023 after the BMA achieved a smaller mandate in the strike ballot. Of 48,000 members, 55% voted, of whom 90% supported industrial action – representing less than half of members – compared with a turnout of 71.25% in 2023, of whom 43,440 (or 98.37%) voted to go on strike.

The numbers of striking doctors is expected to vary between hospitals and trusts, with anticipated staff rota gaps filled locally by consultants, agency doctors and other NHS staff.

Hospital leaders will monitor demand and if they are overwhelmed with patients they will have contingency plans in place, for example cancelling some appointments to prioritise urgent and emergency care, calling in extra bank or agency staff, or requesting derogations – where resident doctors are called in to work – with the BMA.

The Health Service Journal (HSJ) reported that the NHS England chief, Sir Jim Mackey, had told trust leaders to crack down on resident doctors’ ability to earn money during the strike by working locum shifts.