Health workers in England are meant to be fully vaccinated against COVID-19 by April, but Mr Javid has faced growing pressure to get rid of the rule.

He told MPs it is no longer proportionate to require NHS staff and health care workers to be vaccinated.

He defended the initial policy - insisting the government "makes no apology for it".

A letter to NHS England staff seen by Sky News reiterated the vaccine was "the most important defence against the virus" - but told colleagues to hold fire before giving notice to unvaccinated workers.

The British Medical Association (BMA) warned the policy could have inflicted a "devastating" impact on an "already stretched workforce".

President of the Royal College of Physicians, Andrew Goddard, added: "Further loss of staff is the last thing the NHS can afford when it is already experiencing record numbers of vacancies across health care professions."

COVID news live - updates from the UK and across the globe

Mr Javid told MPs it was important to consider the impact on NHS and social care staff, "especially at a time where we already have a shortage of workers and near full employment across the economy".

He added: "In December I argued, and this House overwhelmingly agreed, that the weight of clinical evidence in favour of vaccination as a condition of deployment outweighed the risks to the workforce.

"It was the right policy at the time, supported by the clinical evidence, and the government makes no apology for it. It has also proven to be the right policy in retrospect, given the severity of Delta."

However, former health secretary, Jeremy Hunt, voiced his concerns about Mr Javid's U-turn.

Mr Hunt, health and social care select committee chairman, told the Commons: "Frontline workers have done an extraordinary job in this pandemic but I have yet to meet a single one who believes that anyone who comes in contact with patients has a right to put them to increased risk by not having a vaccine, unless there is a medial exemption.

"My concern is that having marched the NHS to the top of the hill, having actually won a very important patient safety argument, we are now doing a U-turn."

But Mr Javid said it was right to review the policy after Omicron replaced Delta as the dominant COVID strain.

Announcing a consultation, he told the Commons: "Subject to the responses and the will of this house, the government will revoke the regulations.

"I have always been clear that our rules must remain proportionate and balanced, and of course, should we see another dramatic change in the virus, it would be only responsible to review this policy again."

NHS doctor Steve James - who told Mr Javid he would not have the vaccine - told Sky News today that he had not changed his mind.

The consultant anaesthetist believes the "science isn't strong enough" to support mandatory vaccines for NHS workers.

Boris Johnson, speaking during a visit to the Port of Tilbury, in Essex this morning, said he believes it is "absolutely clear" that NHS staff should get vaccinated.

But the Royal College of GPs and Royal College of Nursing (RCN) urged for the deadline to be postponed while the BMA called for an "urgent impact assessment" on how the policy would affect staffing numbers.