Priests will be on hand to offer comfort to those being treated at the NHS Nightingale Hospital and their loved ones.
London's Excel Centre, a vast exhibition hall, is being transformed into a 4,000-bed hospital to treat people infected with coronavirus.
Father James Mackay, of St Anne's in Newham, east London, told The Times that he and other faith leaders had been called in to help the immense operation.
"It's a multifaith operation involving all and sundry: imams, Catholics, Anglicans and others I'm sure," he said.
"We are still in the preparation stage, but our role will be to comfort the sick, deliver the last rites and help those families who have lost loved ones.
"I think there may well be a very big task ahead of us. There are 4,000 beds in there — that's potentially 4,000 dying people."
In addition to doctors and nurses, furloughed staff from EasyJet and Virgin Air - many of whom are trained in first aid - will be serving as carers after the airlines grounded their fleets due to the pandemic.
They will help to change beds and perform non-clinical tasks. Some of the airlines' staff will also help out at the makeshift hospitals being planned for Birmingham's NEC and the Manchester Central conference centre.
Both airlines have said they will pay their staff while they work at the hospitals.