Tougher coronavirus restrictions are being imposed on people living in the Liverpool city region, Warrington, Hartlepool and Middlesbrough.
Health Secretary Matt Hancock said residents in the areas should not socially mix with those from other households – except in outdoor spaces like parks and outdoor hospitality settings.
And he warned against "all but essential travel" – meaning people can still go to work and school.
The changes will come into effect from 12:01am on Saturday.
Mr Hancock said the measures are needed because "in some parts of the country, the virus is spreading fast", with cases shooting up to 268 per 100,000 people in Liverpool.
But the second spike in COVID-19 cases is "highly localised", he claimed, adding recent actions are having a "positive impact".
"What we're doing to respond to these awful circumstances is starting to work, so don't let up," he said in a Commons statement on Thursday.
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"Let's all of us keep doing our bit and one day, over this virus, we will prevail."
Steve Rotheram, the metro mayor for the Liverpool City Region, said the measures are a "step in the right direction" but added he was unsure "whether they are enough".
He called on the government to publish its scientific evidence and provide "substantial" economic support for already-struggling fims.