Prison staff will be offered bonuses to cover shortages - and staff could be redeployed to cover front line services.

A number of inmates died during unrest at several Italian prisons last week after visits were suspended.

The Prison Officers Association has compared conditions in England's prisons to those found on cruise ships and the Prison Governors Association has said cases of the virus are inevitable.

BBC News has seen advice issued to prisons, which says inmates who had contact with a known coronavirus patient should be isolated in single accommodation.

It is understood plans being drawn in up in Whitehall involve communicating regularly with inmates, making sure they can contact their families and providing extra materials - like books and magazines - to those isolating to try to avoid boredom.

The possibility of designating other buildings as prisons to cope with pressures has not been ruled out.

Senior figures do not believe large numbers of prisoners will have to be released to cope with any strain.

There is, however, significant concern about the impact on older prisoners with underlying health issues.

Ministers are thought to have not ruled out releasing vulnerable inmates most at risk, but the instinct in government is that they should serve their sentences.