Health Secretary Matt Hancock has said he "would love to be able to wave a magic wand" to increase supply of personal protective equipment (PPE).
Speaking to a committee of MPs online, he said there was huge global demand for PPE and he didn't know when shortages would end.
A leading nurse has said she is worried about the lack of gowns in hospitals.
Mr Hancock admitted the supply of gowns was "tight" but said he was aiming to get enough gowns to staff this weekend.
"I would love to be able to wave a magic wand and have PPE fall from the sky in large quantities and be able to answer your question about when shortages will be resolved," the health and social care secretary told the committee.
"But given that we have a global situation in which there is less PPE in the world than the world needs, obviously it's going to be a huge pressure point."
He said it was a "global challenge" and the government was doing everything it could to get PPE to front-line workers.
'Team effort on PPE'
There has been mounting criticism from doctors, nurses and care home staff over the lack of face masks and other equipment to protect them when they are caring for infected patients.
The focus will now be on ramping up the manufacture of PPE in the UK, rather than relying on imports from abroad, Mr Hancock indicated.
And he repeated his pleas for UK companies to come forward to help "the domestic effort" to make protective equipment.
He also said there had been a "team effort" on PPE between the four nations of the UK, adding that 11 million items had been shipped from England to Scotland.
Earlier, the head of the Royal College of Nursing, Dame Donna Kinnair, said she was very worried about the shortage of protective equipment, and particularly gowns for nurses in hospitals.
When asked about personal equipment being re-used, Mr Hancock said this was a clinical decision.
However, new advice issued by the Department of Health confirms an earlier BBC report that protective gowns and masks should be reused if there are shortages of PPE, and it is safe to do so.