The UK government’s threat to fire unvaccinated National Health Service (NHS) staff is likely to be delayed amid fears of a Conservative Party revolt against Prime Minister Boris Johnson, according to The Telegraph.

The NHS vaccine mandate will probably be “kicked down the road” and delayed by six months, though not scrapped altogether, an unnamed government source told the publication on Saturday.

The Telegraph reported that the government fears a backbench revolt as some MPs are preparing to file a motion of no confidence in Johnson if he is implicated in the Downing Street parties which allegedly took place last year in breach of Covid-19 restrictions. One source told the newspaper that “a substantial number” of government ministers and MPs would be willing to vote no confidence in Johnson.

Disaffected Conservative backbench MPs have called for the NHS vaccine mandate to be repealed, arguing that it would cause further staff shortages at a time when the health service is already under major pressure.

Hundreds of NHS staffers and their supporters took to the streets of London on Saturday in protest over the mandate, holding signs which read, “My Body My Choice,” “No NHS Mandates,” and “From Clapping to Sacking” – the latter in reference to the weekly applause NHS staff received in 2020 for their pandemic efforts.

Under the current mandate, NHS workers have until April 1 to get fully vaccinated against Covid-19 or face being fired. Those who have not received their first jab by February 3 will reportedly be informed of their dismissal. ITV reports that as many as 70,000 NHS employees remain unvaccinated.