The company operates all 15 nuclear reactors in Britain. Currently eight of those, with a combined capacity of around 4.2 gigawatts - almost half of the country's total nuclear power capacity - are offline for planned or unplanned outages.

"We have comprehensive plans in place to maintain operations at all of our power stations and planned generation is not affected at any of our sites," said a spokeswoman, declining to specify what the measures were.

On Monday, EDF Energy's parent company EDF said it would reduce staff at its Flamanville nuclear power plant in northern France due to coronavirus infections in the Cotentin region. The plant has been offline for maintenance.

Britain's Office for Nuclear Regulation (ONR) said all UK sites have minimum staffing levels, and contingency plans should they fall below these levels, to enable them to stay in control of activities that could affect nuclear safety under all foreseeable circumstances.

The ONR, which is in charge of overseeing nuclear safety, said its staff have been directed to work at home.

"A number of inspectors will continue to travel to sites where required, but we will endeavour to carry out as much of our business as possible via phone, email and Skype," it said.

"These measures will not have a severe impact on our regulation of the nuclear industry."

By Nina Chestney