Speaking outside No 10 Downing Street on Monday, Boris Johnson urged Britons "to contain" their "impatience" because it is too soon to ease down lockdown measures.

"We cannot risk losing control of that virus... because that would mean not only a new wave of death and disease but also an economic disaster," he said.

The United Kingdom has been under lockdown for five weeks, since 23 March, leaving the economy facing its worst recession in three centuries, experts say.

For Johnson, Covid-19 is "the biggest single challenge this country has faced since the war".

EY Item Club forecasting group predicts it will need three years to recover from the fallout of the coronavirus pandemic.

Johnson said that lifting the lockdown too soon will cause lasting damage to the economy.

The UK is among the five worst hit countries with 20,732 Covid-19 related deaths as of Monday 27 April. But health specialists say that the country's total death toll is much higher as statistics for deaths outside hospital, for example in care homes, are slower to be published.

Johnson returned to Downing Street on Sunday night while his government is facing pressure over its handling of the epidemic.