Boris Johnson has imposed a third national lockdown on England to prevent a surge in coronavirus cases In a televised address to the nation last night, the prime minister said to stay indoors as much as possible - with measures expected to last until mid-February.

Schools, secondaries and colleges will move to remote teaching for most students from today.

Mr Johnson said the new variant is 50 per cent to 70 per cent more transmissible.

He added: "As I speak to you tonight, our hospitals are under more pressure from Covid than at any time since the start of the pandemic."

Mr Johnson's statement came after the chief medical officers for the first time raised the UK to the highest level on the Covid-19 alert system, meaning the NHS is at risk of being overwhelmed within 21 days.

The restrictions are unlikely to be eased until around 13 million people aged over 70 or classed as clinically extremely vulnerable have received the vaccine.

Exercise will be permitted with household or support bubble members or with one other person from another household, but is advised to be limited to only once per day and carried out locally.

The remaining exceptions to going outside are to seek medical help, provide assistance to a vulnerable person, to receive medical care or to flee a threat of harm.

Non-essential shops will have to close, but early years settings such as nurseries and childminders are allowed to remain open and childcare bubbles can stay in place.

Exams will again face disruption as schools close to all those other than for the children of key workers and vulnerable children until after the February half-term.

Restaurants and other hospitality venues can continue delivery or takeaway services but will no longer be permitted to serve alcohol.

The clinically vulnerable who were previously told to shield should stay at home and only leave for medical appointments and exercise.