Using inoculations as "wall of defence", the UK announced plans to further relax to its pandemic curbs on Tuesday despite warning that the number of daily new cases is set to more than treble to reach 100,000.
From August 16, adults in England who have received both doses of a coronavirus vaccine will no longer need to self-isolate if they are in close contact with a positive case, health secretary Sajid Javid said.
Instead they will need to take a test and isolate only if they are found to be positive, he told parliament.
The same rules will apply to under 18s, who are not yet receiving vaccinations in Britain, Javid added.
The rules will come in ahead of the return to school for the September term, after months in which entire classes have been sent home to the fury of parents.
The health secretary was updating MPs a day after prime minister Boris Johnson revealed plans to lift most of England's coronavirus restrictions, including face masks and social
distancing, from July 19, urging personal responsibility rather than government edict.
As part of devolved administration, Scotland, Wales and Northern Ireland set their own health policy and are moving more slowly.
Johnson had initially aimed for a full reopening on June 21, but was forced to push back the
date because of a surge in the highly contagious Delta variant.
That variant now accounts for nearly all new Covid-19 cases in Britain, and daily infection
rates have soared to nearly 30,000 in recent days.
Javid said that figure was likely to reach 50,000 a day by July 19, and as high as 100,000 later in the summer.
But the vaccination campaign has "weakened" the link with hospitalisations and deaths, he
stressed to MPs, saying that inoculations are "our wall of defence".
More than 86 percent of adults in the UK have received at least one jab, with 64 percent fully vaccinated, according to NHS data.
He also responded to media reports that three batches of the AstraZeneca jab made in India have not been approved for use in the EU, potentially hindering summer travel for British recipients of those doses.
Britain has not been using the Covishield-branded jab made by the Serum Institute of India, and the government is in "intensive discussions" with Brussels on the issue, Javid said.
