"Things look pretty grave at the moment and the numbers are going up pretty rapidly," John Bell, a government adviser and immunologist, told BBC Radio 4. Bell, who is also a professor of medicine at Oxford University, acknowledged that people are "pretty unhappy" and tired of existing restrictions. Nonetheless, he highlighted the importance of imposing tougher measures against Covid-19.British officials have previously hinted that a second nationwide lockdown remains on the table as a 'nuclear option,' but the government is determined to do its best to avoid the worst-case scenario.

UK media reported earlier this week that back in September the government's Scientific Advisory Group for Emergencies (SAGE) warned about a "very large epidemic with catastrophic consequences" unless a two-week "circuit-breaker" lockdown was imposed immediately. Prime Minister Boris Johnson, however, opted for a three-tier system of local lockdowns, combined with stricter rules on mask-wearing and large gatherings, as well as additional measures like curfew on pubs.

On Wednesday, the PM defended his decision against a second nationwide lockdown in parliament, without ruling out the option completely. "The whole point is to seize this moment now to avoid the misery of another national lockdown," Johnson said, arguing that a "regional approach" will get the spread of the disease under control.

The UK has seen a dramatic surge in Covid-19 cases since September, with the total caseload growing to 689,257, according to the government. Overall, 57,690 people have died since the start of the outbreak.