Greater Manchester mayor Andy Burnham is to hold talks with No 10 amid mounting expectation the region will be the next to face the toughest coronavirus controls.
Mr Burnham has been resisting pressure to follow the Liverpool City Region into the Tier 3 restrictions – which would see bars, gyms and betting shops forced to close – despite soaring infection rates.
However following a briefing with the deputy chief medical officer for England Dr Jenny Harries on Wednesday, he said he expected to have a further meeting with Boris Johnson's team on Thursday.
The move came amid reports the Government's Joint Biosecurity Centre had recommended most of the North West and North East of England, as well as parts of Yorkshire and the Midlands, should be moved into Tier 3.
With Greater Manchester and Lancashire looking set to be the first to be affected, Manchester MPs said they had been invited to a meeting on Thursday morning.
Lucy Powell, the Labour MP for Manchester Central said it had "all the hallmarks of a decision having been made".
Mr Burnham reacted angrily to the reports, tweeting: "At no point during tonight's briefing was this news communicated to us. Media told first once again. Our position has not changed."
In contrast, London mayor Sadiq Khan has said he would back tighter restrictions in the capital – which is currently under the lowest Tier 1 controls – but called for a package of financial support for the city.
In a letter to the Prime Minister, he said that with the infection rate approaching approaching 100 cases per 100,000 head of population, new measures would be needed "very soon" – possibly as early as this week.
Health Secretary Matt Hancock will update MPs on the latest measures in a Commons statement later on Thursday.
Meanwhile, Northern Ireland is braced for the toughest controls in the UK so far with pubs and restaurants set to close for four weeks from Friday and schools facing a two week shutdown.
And the UK Government described a decision by the Welsh Government to ban travel to the country from other parts of the UK with high levels of coronavirus infection as "disappointing".
Mr Johnson remains desperate to avoid any form of national lockdown – despite demands from Labour for a temporary "circuit-breaker" to break the train of transmission and stem the spread of the disease.
In the Commons on Wednesday, he urged Labour leader Sir Keir Starmer to use his influence with Labour authorities in the North to agree to "stringent measures" to get the rates down.
But in an online press conference, Mr Burnham said that if Greater Manchester was placed into Tier 3 it would be "by imposition, not consent".
He warned that he could take legal actions to ensure residents were protected from the economic fallout of tougher restrictions.
"We are law abiding people, we would respect the law of the land," he said.
"But we would consider other routes, legal routes, where we could protect our many thousands of residents who are going to be left in severe hardship in the run up to Christmas."
In contrast, in Lancashire, Tory county council leader Geoff Driver said it was "inevitable" his region would be entering Tier 3.
In his letter to the Prime Minister, Mr Khan said that a shortage of testing capacity in the London meant a move to Tier 2 – with a ban on households mixing – appeared inevitable.
"With the London rate fast approaching 100 cases per 100,000 and on the increase, it is likely that we will move to high alert level very soon, possibly this week," he wrote.
"None of us want more restrictions in London but given the increase in infection rates and the lack of testing we have little choice."
Meanwhile Sir Keir is continuing to press for national "circuit-breaker" following the disclosure that the Government's Scientific Advisory Group for Emergencies had recommended such a move last month.
He was bolstered by a YouGov poll showing 68% of adults in Great Britain would support a two-week shutdown to coincide with the October half term break.