Dozens of stations on the London Underground subway system have been closed as the city's mayor urges people in the city to restrict travel amid the COVID-19 pandemic.

CNN and BBC report that 40 stations along London's Tube system have been closed. Transport for London (TFL), who operates the Tube, will also suspend night service on weekends.

On Thursday, London Mayor Sadiq Khan said that Londoners should avoid "using the transport network unless absolutely necessary."

According to a database kept by Johns Hopkins Univesity, the UK has confirmed at least 2,644 cases of the novel coronavirus. Of the 104 deaths linked to the virus in the UK, as of Thursday, at least 30 occurred in the London area.

Earlier this week, British Prime Minister Boris Johnson said that COVID-19 was spreading faster in London than it was in other parts of the United Kingdom.

On Wednesday, when asked about ordering citizens to stay indoors to prevent the spread of the virus, Khan said that the city is "not there yet," but would consider bans to stop people from gathering in bars.