Tougher lockdown measures have been introduced in parts of northern England after a rise in the rate of novel coronavirus transmission, raising concerns over a second wave.
Britain reported its highest number of new COVID-19 infections in more than a month on Thursday, as ministers warned more quarantine restrictions were possible.
Around 4 million people were ordered not to mix with other households in Greater Manchester, the biggest city in northern England, parts of West Yorkshire and East Lancashire, though they can still go to work.
Those breaking the rules will face a fine of 100 pounds.
"The problem with this virus is that it thrives on the social contact which makes life worth living," Health Secretary Matt Hancock told Sky. "I totally understand the human impact of this but unfortunately that is how the virus passes on."
Asked by the BBC if the UK was now entering a second wave, Hancock said: "It is not yet and we are absolutely determined to take the action that is needed."
The measures were introduced hastily at the start of Eid al-Adha.
A Ukrainian F-16 fighter pilot died in a crash while repelling a Russian air attack that involved hundreds of drones, cruise and ballistic missiles, authorities said on Sunday, as Moscow intensifies night-time air barrages in the fourth year of war.
Two firefighters were shot dead while responding to a fire in northern Idaho and the body of a man was later found with a gun nearby, the Kootenai County Sheriff's Office said on Sunday, as it lifted a shelter-in-place order.
Iran could be producing enriched uranium in a few months, the head of the UN nuclear watchdog Rafael Grossi was quoted as saying on Sunday, raising doubts about how effective US strikes to destroy Tehran's nuclear programme have been.
The Jerusalem District Court has cancelled this week's hearings in Prime Minister Benjamin Netanyahu's long-running corruption trial, accepting a request the Israeli leader made citing classified diplomatic and security grounds.
The Israeli military ordered Palestinians to evacuate areas in northern Gaza on Sunday before intensified fighting against Hamas, as US President Donald Trump called for an end to the war amid renewed efforts to broker a ceasefire.