Millions more people in England will be subject to tougher coronavirus restrictions that could last at least four months, Boris Johnson has warned, as northern leaders said they would fiercely resist a return to the highest tier. The prime minister is expected to unveil plans on Tuesday to let a limited number of households mix indoors for up to five days over Christmas. However, he cautioned that people “will need to make a careful judgment about the risk of visiting elderly relatives”. It was also confirmed that the test-and-trace system will get a £7bn funding boost, taking it cost to £22bn this year, as part of an expanded programme of mass testing. England will emerge from national lockdown into a fresh, tiered system of controls from 2 December, Johnson confirmed to the Commons on Monday. Millions are set to enter or re-enter tier 3 curbs, under which pubs and restaurants will remain closed and restricted to takeaways. In tier 2, hospitality businesses will only be allowed to serve alcohol with a “substantial meal”. Johnson warned that “more regions will fall – at least temporarily – into higher levels than before” when details are finalised on Thursday. Before the decision is announced, leaders in north-west England are expected to argue that cases there are slowing dramatically compared with in London and the south-east. Unlike under the previous system, there will be no negotiation with local leaders, in an attempt to prevent a repeat of bitter public disputes. Financial support will be allocated on a uniform per-capita basis following a damaging row with the Greater Manchester mayor, Andy Burnham. Dan Jarvis, the mayor of the Sheffield city region, said the system could not continue to disproportionately affect the poorest regions without negotiation with local leaders, or it would risk losing trust. “This pandemic has hit some of the most disadvantaged parts of the country the hardest. Many of those parts may now be asked to remain under serious restrictions while the rest of the country faces a lesser burden,” he said. “We’re willing to do our bit, but we must not be taken for granted. We’re already sacrificing a great deal when we can ill afford it. “Consistency and fairness is the essential condition of all of this. You can’t refuse to negotiate with local governments but then say lockdowns are a matter of judgment. You can’t refuse to negotiate and then not give us the support we need. You have to get it right.” Ministers are likely to face questions over the north-south divide in restrictions unless areas in southern England are subjected to tougher measures. In the latest figures, London is one of only two regions where a majority of areas have recorded a rise in cases. Of the 32 areas in London, 20 showed an increase, with the biggest jumps in Havering, Enfield and Redbridge. Kent, where cases are rising most rapidly, is also at risk. The south-east is now the region with the highest coronavirus rates in England – they are rising in 34 out of 67 local authority areas. The Labour MP Rosie Duffield, whose Kent constituency borders Swale, which has overtaken Hull in east Yorkshire to become England’s worst-hit local authority, said it was “clear that previous measures have failed to stop the rise in cases”. She said the county should prepare for tough restrictions but the government needed to give “further clarity about how areas enter and exit particular tiers”. London leaders are expecting the capital to be in tier 2, and the mayor, Sadiq Khan, is likely to resist tier 3 unless there is compelling data. One London MP said Tories were “fiercely lobbying” the government to allow hospitality to remain open in the capital. Judith Blake, the leader of Leeds city council, said “all northern core cities are expecting to be in tier 3 – with a review in two weeks”. But Liverpool’s Labour mayor, Joe Anderson, said his city should not re-enter tier 3, given the infection level was down to less than 200 per 100,000 people, down from 700 six weeks ago. “The pressure is off hospitals, they’re down to around 80% occupancy in the Covid wards and round about 80% in the ICUs … So looking at the figures as they are today, I’d be arguing that we are in tier 2 territory,” he said. Burnham, who fiercely resisted his region being placed in tier 3 in October, said the toughened version of the tier would devastate the city, suggesting he would lobby hard for his region to be downgraded. “A toughened tier 3 could be devastating for the hospitality industry and will hit cities and the city economy very, very hard indeed,” he told the BBC. “They seem to be going too far before Christmas to allow too much over Christmas and that will lead to a huge loss of hospitality businesses, which I would say is too big a price to pay. To close all hospitality businesses in tier 3 areas – that will be large parts of the north – that will be devastating for many of those businesses. They will not survive that.” Tier positions will be reviewed every 14 days and will be based on five criteria: case numbers across all age groups, cases in those aged over 60, the rate of rise or fall in infections, the percentage of those tested who have the virus, and current and projected pressures on the NHS locally. Johnson is likely to face a tough day in Westminster when the levels of restrictions are announced, with a number of backbench MPs seeming sceptical of the proposals. Mark Harper, who chairs the Covid Recovery Group of MPs critical of harsh lockdown measures, said those with areas in tier 3 would “struggle to spot much of a difference from the lockdown”. Keir Starmer warned Johnson there were “huge gaps … huge uncertainties and huge risks” in the plan and suggested more detail would be needed for Labour to back the plan. MPs will vote on the measures early next week. Chris Whitty, the chief medical officer for England, said people should take the opportunity to see family over Christmas but do it “incredibly responsibly”. He said “of course” the relaxation of rules over Christmas would have an impact on infections. “If everyone is serious before during and after, then we can minimise the amount of impact it will have, [but] of course it will have an impact”.