Boris Johnson is spending the weekend considering whether to tighten Covid-19 measures in England, after saying the UK was “now seeing a second wave”.
The government is understood to be looking at a ban on households mixing, and reducing opening hours for pubs.
At least 13.5 million people, roughly one in five of the UK population, are already facing local restrictions.
It came as the PM announced new fines for those avoiding self-isolation.
Former government adviser Prof Neil Ferguson said new measures were needed “sooner rather than later”.
The scientist, whose advice was crucial to the decision to go into lockdown in March, said: “If we leave it another two to four weeks, we will be back at [infection] levels we were seeing more like mid-March.
“That’s clearly going to cause deaths because people will be hospitalised,” he said.
Read more: BBC News