Covid: Final stage of lockdown easing in England to be delayed by a month
The prime minister will make an official announcement on the delay on Monday.
The final stage of the government's roadmap out of lockdown is set to be pushed by back four weeks, according to reports.
All legal restrictions on social contact in England were due to end on June 21, but government sources have told the BBC that senior ministers have signed off on the decision to delay this.
It comes amid increasing concern about the rise in infections across the country and the spread of the Delta variant which was first detected in India.
Boris Johnson will announce the news of the delay in a press conference later on Monday. He will also set out the details of the new planned easing of restrictions.
The decision is expected to face significant rebellion from backbench Tory MPs who are adamant that lockdown restrictions should be lifted as soon as possible.
The announcement is also disappointing news for businesses such as nightclubs, which had been building towards the 21 June as the date they would be allowed to reopen for the first time since March 2020.
Former government chief scientific adviser, Sir Mark Walport, spoke to BBC Radio 4 about why the delay of the ending of all restrictions is required.
He said: "It is a race between the vaccination and the virus, and another four weeks makes a significant difference.
"It will also help us really establish the extent to which the vaccination breaks or weakens the link between getting an infection and getting the serious effects of ending up in hospital or potentially dying.
"So we'll get a lot more information, we'll see what's happening with hospital admissions, which of course lag [behind] infections."
There is speculation about whether a "break clause" may be included in the new plans.
Former Conservative cabinet minister, Damian Green, told the BBC's Westminster Hour that he wanted to see the decision to delay reviewed as more data becomes available.
"If it is as long as a month then there should be a break clause after two or maybe three weeks, to say that if we can tell by then that the rise in cases is not leading to a rise in the serious illness that sends people into hospital, then we can unlock earlier," he said.
The Delta variant has caused a significant rise in cases over recent weeks. The variant is thought to be around 60 per cent more infectious than the Alpha variant that was discovered in Kent at the end of last year and became the dominant strain of the virus in the country.
It is now thought that the Delta variant accounts for 90 per cent of infections in the UK now, and the seven-day average for cases in the UK is up 49 per cent compared with the seven days prior.
There has been rising pressure from scientists and medical experts for the crucial June 21 date to be delayed because of the rise in infections.