British Prime Minister Boris Johnson (R) leaves 10 Downing Street in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates. (Photos: Xinhua)

A customer and a shopper wearing face masks are seen in a shop in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.

Customers wearing face masks walk out of a shop in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.

Photo taken on Oct. 12, 2020 shows a pub in London, Britain. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.

A man wearing a face mask walks past a shop in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.

People wearing face masks walk past a shop in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.

A customer wearing a face mask purchases fruits in a shop in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.

A woman wearing a face mask walks past a restaurant in London, Britain, on Oct. 12, 2020. British Prime Minister Boris Johnson on Monday announced a new three-level COVID-19 alert system that will be implemented across England, with Liverpool moved to the highest tier as the level being decided according to local infection rates.