Medical staff may refuse to work this weekend if there are not enough gowns and other personal protective equipment (PPE) for them, a union has warned.

Matt Hancock, the health secretary, has said he cannot guarantee hospitals will have enough PPE to get through the next few days.

In a major shift, doctors and nurses were asked to treat patients without full length waterproof gowns, where necessary, and even use plastic aprons as an alternative.

Sara Gorton, head of health at the union Unison, said: “Health managers must be truly honest with their staff … over the weekend. If gowns run out, staff in high risk areas may well decide that it’s no longer safe for them to work”.

Chris Hopson, chairman of NHS Providers, said some trusts will run out of supplies in the next 24-48 hours because we have “reached the point where national stock of fully fluid repellent gowns and coveralls (is) exhausted”.

A British Medical Association (BMA) survey of more than 6,000 doctors across the UK found a significant number are without PPE.

A separate survey by the Royal College of Nursing (RCN) also found half of nurses have felt pressure to work without appropriate protective equipment.

BMA council chairman Dr Chaand Nagpaul said: “Two months into the Covid-19 crisis in Britain, we shouldn’t still be hearing that doctors feel unprotected when they go to work.”

The BMA survey found just under a third of doctors said they were sometimes pressured to work without adequate protection.

Half of doctors in high risk areas said there were shortages of long-sleeved disposable gowns and disposable goggles.

Dr Nagpaul added: “Too many doctors and healthcare staff have already lost their lives. We cannot afford to risk losing any more.”

Around 50 NHS workers have now died after contracting coronavirus.