The UK government came under increasing pressure on Friday as its three-tier COVID-19 lockdown faced backlash from some regions, even as Londoners prepared to move into Tier 2 high-risk category from Tier 1 medium level from midnight as part of efforts to control infection rates.

UK Foreign Secretary Dominic Raab accused the local authorities of Greater Manchester in northern England of holding the centre "over a barrel" after the region's mayor, Andy Burnham, refused a third-tier categorisation akin to a complete lockdown without additional funding support for local businesses.

"Ultimately we need to take action; we can't have a situation as we have seen in Manchester where Andy Burnham is effectively trying to hold the government over a barrel over money and politics," said Raab.

"I would just urge Andy Burnham to do the right thing by the people of Manchester," the minister said.

However, Opposition Labour's Burnham has stood firm that being forced into the third tier without a substantial financial package would be disastrous for the local economy.

"It's not about what we want for ourselves. It's about what we want for low-paid and self-employed people everywhere: fairness," Burnham tweeted in response.