Britain began its third Covid-19 lockdown with citizens under orders to stay at home and the government calling for one last major national effort to contain the virus before mass vaccinations turn the tide.

Prime Minister Boris Johnson announced the lockdown late on Monday saying the highly contagious new coronavirus variant first identified in Britain was spreading so fast it risked overwhelming the National Health Service (NHS) within 21 days.

In England alone, some 27,000 people are in hospital with Covid, a number 40 per cent higher than during the first peak of infections in April, Reuters reported.

“The weeks ahead will be the hardest yet but I really do believe that we are entering the last phase of the struggle, because with every jab that goes into our arms, we are tilting the odds against Covid and in favour of the British people,” said Johnson.