Mask rules will be mandatory in shops and on public transport, Omicron contacts will have to self-isolate and new arrivals will have to quarantine until they test negative for coronavirus, after two cases of the concerning new variant were detected in the UK.

Prime-Minister-Announces-Introduction-Of-New-Measures-Follow

The rules relating to shops and public transport will come in from next week but hospitality will be exempt.

Prime minister Boris Johnson warned the new variant could reduce the effectiveness of vaccines, as he announced a strengthening of England's rules at a Downing Street press conference, after the infections were identified in Nottingham and Brentwood in Essex.

In an attempt to slow the spread, the PM announced "temporary and precautionary" measures to be reviewed in three weeks, alongside a "boost" to the booster campaign.

Face coverings will become compulsory in shops and on public transport from "next week", a statement from 10 Downing Street said.

The statement, which was issued following the prime minister's press conference, said: "Face coverings will be made compulsory in shops and on public transport from next week. All hospitality settings will be exempt."

Mr Johnson told the Downing Street press conference: "On face coverings, what we're looking at is retail and transport, just going back to a position where you have to wear them in retail settings or on public transport.

"But the Health Secretary Saj (Javid) will be setting out more in the course of the next day or so."

Mr Johnson stopped short of bringing back the work from home guidance or extending the use of vaccine passports.

England's chief medical officer Professor Chris Whitty said the Joint Committee on Vaccination and Immunisation (JCVI) will be tasked with looking at whether boosters can be extended down from the over-40s to the over-18s.

The experts will also consider whether second doses should be offered to 12 to 15-year-olds, and the wait before a booster jab could also be reduced.

Mr Johnson said he is "confident" Christmas "will be considerably better than the last", which was largely cancelled for millions of people, but he refused to say whether further restrictions could be imposed.

The UK Health Security Agency confirmed the cases, which are both believed to be connected and linked to travel to southern Africa, after genomic sequencing overnight.

The individuals and their households were ordered into self-isolation and targeted testing was being carried out in areas where they are thought to have been infectious

Malawi, Mozambique, Zambia and Angola will face travel restrictions from Sunday, when they will join South Africa and five other neighbouring nations on England's red list.

Mr Johnson said: "We need to take targeted and proportionate measures now as a precaution while we find out more.

"First we need to slow down the seeding of the variant in this country, we need to buy time for our scientists to understand exactly what we're dealing with, and for us to get more people vaccinated, and above all to get more people boosted."

But the prime minister said border measures can "only ever minimise and delay the arrival of a new variant rather than stop it all together", so all contacts with a suspected case of the new variant will have to isolate for 10 days, regardless of their vaccination status.

"We will also go further in asking all of you to help contain the spread of this variant by tightening up the rules on face coverings in shops and on public transport," Mr Johnson said.

While the effectiveness of vaccines against Omicron is currently unclear, Mr Johnson said there are "good reasons for believing they will provide at least some measure of protection".

He said "we're going to boost the booster campaign" by asking the Joint Committee on Vaccination and Immunisation (JCVI) to consider giving boosters to "as wide a group as possible as well as reducing the gap" between second doses and the booster.

The prime minister admitted the latest restrictions on travel "sound tough", but added: "That's the way it's got to be."

In response to a question about whether the Government could have moved faster to close borders to protect the country from the new Omicron variant, Mr Johnson said: "I really don't know how we could've acted faster.

"We got the news out about it on Thursday and we put quite a lot of southern African countries on the red list yesterday, and some more today."