‘Support bubbles’ mean adults living alone can join another household from Saturday

Announcing the development, Mr Johnson said: “We are making this change to support those who are particularly lonely as a result of lockdown measures. It’s a targeted intervention to limit the most harmful effects of the current social restrictions.

“It is emphatically not designed for people who don’t qualify to start meeting inside other people’s homes, because that remains against the law.”

The new policy will not apply to those who have been shielding, however, and the Prime Minister said: “Unfortunately, we cannot advise anyone who is shielding to form a support bubble at this stage, given their particular vulnerability to the virus.”

He said the Government will “say more next week” about the arrangements that will be in place for those shielding after the end of June.

On Wednesday, Downing Street said the measure was not going to benefit everyone and has been targeted at those left isolated by the lockdown.

For example, if you live with a partner you will not be able to form a bubble with your parents, provided they live together. For a support bubble to qualify, one household must have just one adult in it.

Professor Chris Whitty, the chief medical officer, said: “The bubbling is about single households or lone parents.”

This could mean families may need to choose a grandparent to form a bubble if they have more than one living apart from them. It would also mean a person who has been living alone during the lockdown having to choose between forming a bubble with their partner or their parents.