This new variant is a reminder for all of us that the pandemic is far from over, the health secretary continues.

He tells MPs "we must do all we can to keep the virus at bay" - and stresses the importance of getting the booster jab.

The UK has already given 16 million boosters.

"The booster jab was already important before we knew about this variant," Javid says.

"But now, it couldn't be more important."

• Read more: Who can get a booster jab now?

Image source, ParliamentLive.TV

Javid continues by thanking the South African government - which held a press conference on the new variant yesterday - for their "rigorous scientific response" and the "openness and transparency" of their actions in relation to the new Covid strain.

He says the government is deeply concerned this new variant may pose a "substantial risk" to UK public health - as it has an "unusually large number of mutations".

Yesterday, the UK Health Security Agency classified the new variant, b11.529, under investigation, he says.

And he adds, the variant technical group has classified it as a variant under investigation with very high priority - which he says is the only variant with this designation.

Meanwhile, away from the UK, the World Health Organization (WHO) is holding a special meeting to consider the significance of the rapidly spreading new coronavirus variant in South Africa.

Experts in Geneva will decide whether it should be designated a variant of concern.

The WHO says it will issue new guidance after the talks, but has warned that it will take weeks to establish how transmissible the variant is - and whether vaccines remain effective against it.

As the meeting gets under way, a WHO spokesman says the organisation is currently cautioning against imposing travel restrictions and advised governments to apply "a risk-based and scientific" approach.

Image source, House of Commons

The new variant of coronavirus is of "huge international concern", the UK Health Secretary Sajid Javid tells MPs.

He says it's a "fast-moving" situation with a "high degree of uncertainty".

Speaking in the Commons, he says the UK was the first country to "identify the threat of the new variant" - but adds that there are no detected case of the variant in the UK at the moment.

• Read more: How worried should we be about the new variant?

Sajid Javid is on his feet in the House of Commons and is updating MPs on the latest Covid developments.

Stick with us as we bring you his key points.

Karen Schoonbee
BBC News, Cape Town

Image source, Getty Images

The morning flight from London to Cape Town had both South Africans returning home and Britons who said they had come to visit friends and enjoy the good weather in the Cape.

Some were unaware of the new travel restrictions imposed back in the UK while they were airborne.

One passenger told the BBC that the atmosphere at the front of the plane was subdued when people heard about the new measures. He said there was no big commotion.

A number of passengers said they had not heard anything about the restrictions.

One distraught Capetonian was at the airport to collect her UK-based sister who flew out for their mother's funeral. She said it was "absolutely ridiculous" that travel restrictions had been imposed "again so quickly".

She was happy her sister was on the flight – which may be the last for a while – but said: "I think she'll be staying here for a long time."

Reactions among the UK-based passengers varied. Some said they would simply stay longer and enjoy the good weather, while others said they were surprised and upset to be caught in a travel ban so recently lifted.

Image source, UK Parliament

Health Secretary Sajid Javid will begin updating MPs on the latest Covid situation shortly.

He's due in the Commons at 11:00 GMT - we'll bring you all the updates as they happen.

His opposite number Jon Ashworth won't be there though as he's self-isolating after testing positive for the virus.

South Africa's official government account has tweeted that it can "crush the power of the new variant by vaccinating to limit the number of mutations".

It says that "working together" the country can win the fight and "save our summer because vaccines can fight variants".

The tweet was accompanied by an infographic that outlines the benefits of getting the jab.

Less than a quarter of South Africans are fully vaccinated at present.

Image source, Getty Images

The new Covid variant detected in South Africa has led to countries restricting travel from the southern Africa region.

Cases of B.1.1.529 have been documented in South Africa, Hong Kong, Botswana and Israel.

So far the following countries have imposed curbs on travel from southern Africa:

• The UK has placed restrictions on six countries including South Africa, Namibia, Zimbabwe, Botswana, Lesotho and Eswatini
• Singapore has placed seven countries on its red list despite saying it has no cases of the new variant
• Japan has implemented restrictions from six countries, according to a local news source
• Israel has barred South African travellers and banned its citizens from visiting seven countries in the southern African region
• Germany is banning travel from South Africa allowing only German nationals to enter the country
• Italy has barred entry to anyone who has visited southern African countries in the last two weeks
• The Czech Republic has also put in place a ban which takes effect on Saturday

Shadow health secretary Jon Ashworth is self-isolating after testing positive for Covid.

He tweeted, external: "While huge strides have been made [there is] still a lot of virus circulating.

"So get your jab and booster, do routine lateral flow tests, wear masks in crowded places & govt fix sick pay & ventilation!"

Two rugby teams are trying to return home to Wales from South Africa, which has been put on the UK's red travel list amid concern over the new variant discovered there.

Cardiff and Scarlets were due to play games in South Africa as part of the United Rugby Championship (URC) - but are now searching for a route back to the UK.

Direct flights to England from South Africa - along with Namibia, Zimbabwe, Botswana, Lesotho and Eswatini - will be temporarily suspended from midday.

The Welsh government has adopted the same travel rules as England and any direct flight into the UK from South Africa would usually land in England.

The flights are being suspended until a hotel quarantine system is in operation. Travellers arriving from red list nations after 04:00 GMT on Sunday will be required to quarantine in a hotel.

The rugby teams are exploring trying to return home today, before the quarantine deadline, with charter flights being considered.

• Read more: The red list and other UK travel rules

James Gallagher
Health and science correspondent, BBC News

One scientist told me this was the worst variant they'd seen - look at it on paper and it's not hard to see why.

It is the most heavily mutated variant so far and is now radically different to the form that emerged in Wuhan, China.

That means vaccines, which were designed using the original, may not be as effective.

And some of its mutations are known to increase the ability of coronaviruses to spread.

But there have been many variants that looked bad on paper before, but haven't taken off.

There are early signs this virus is spreading in South Africa and may already be in every province in the country.

But the big questions - how much does it evade vaccines, is it more severe, does it spread faster that Delta - are unanswerable for now.

Read more from James.

Image source, Reuters

The new Covid variant identified in South Africa "could be a setback", but should not cause people to panic, according to a leading scientist.

Prof Francois Balloux, an epidemiologist and director of University College London's Genetics Institute, tells the BBC that because the variant has been detected so early, it could be easier to contain.

He adds that even if the strain is more transmissible, it would not "bring us to square one" in the fight against the virus.

"It's annoying, it's problematic, but it's not like a new pandemic," he says, adding that "entire immunity" will not be lost overnight.

"It could be a setback, but it's not a complete start again of the whole thing."

Read more about the new variant here.

Image source, Getty Images

The head of the agency leading Africa's response to the coronavirus pandemic says imposing restrictions such as banning flights is unlikely to reduce the spread of the new variant.

"The restrictions imposed always make it difficult to co-ordinate a response," Dr John Nkengasong, director of the Africa Centres for Disease Control and Prevention, tells BBC Newsday.

"It doesn't help... it has never helped reduce the spread of any variant across the world," he says, referring to the decision by the UK to suspend flights from six southern African countries.

He suggests abiding by public health measures such as wearing masks, especially at gatherings during the winter festivities, and washing hands.

"Avoid crowds and implement the basic public health and social measures that are effective against all variants. I think that is what we should be promoting."

The appearance of a new Covid-19 variant is nothing new, but where do they come from and at what point to they become a cause for concern?

Image source, Reuters

"It's always possible," says Dr Susan Hopkins, the chief medical adviser to the UK Health Security Agency.

South Africa, Hong Kong, Botswana and Israel all have confirmed cases of the variant, but the UK has not found any yet.

Dr Hopkins says the UK is sequencing more than 50,000 virus cases per week - "a huge amount".

She adds that one of the mutations in the variant is very similar to one of the mutations in Alpha, which means it can be detected quite easily with many of our PCR tests.

"Overall, I think the situation is reassuring in-country, but of course, people are arriving every day," she tells BBC Radio 4's Today programme.

• Read more: What do we know about the new variant?

Image source, Getty

The new variant identified in South Africa is the most worrying we've seen yet, says the chief medical adviser of the UK Health Security Agency, Dr Susan Hopkins.

The epidemiologist says the R value in Gauteng, where the new variant was found, is now at 2 - which is "really quite high".

If you need a reminder - the R value is the number of people that one infected person will pass on a virus to, on average. So in Gauteng, each infected person is on average passing it on to two more people.

"We haven't seen levels of transmission like that since right back at the beginning of the pandemic because of all the mitigation and steps we've taken," she tells BBC Radio 4's Today programme.

"So that would cause a major problem if you had that high transmission with this type of virus, in a population where it may evade the immune responses that are already there."

Image source, AFP

Dr Mike Tildesley, a member of the Scientific Pandemic Influenza Modelling group (Spi-M), which advises the UK government, has said it is "very, very early days" in understanding the new variant and whether it may affect vaccines, whether it spreads more rapidly or is more deadly.

He tells BBC Breakfast: "I think there's been fewer than 100 confirmed cases in South Africa and elsewhere so far, so it is concerning, but really important that we gather as much information as possible right now so we really understand exactly how concerned we should be."

He adds that South Africa could see a rapid spread in cases owing to the fact only 24% of the population are fully vaccinated.

The key thing for the UK, he continues, is whether the variant will send the reproductive value (the R) significantly above one, or would potentially lead to higher numbers of hospital admissions.

He says then the government would need to look at taking action but adds: "There's an awful lot of ifs at the moment and all of these needs to be clarified before I think we get there and actually think about what might be happening if we start seeing a growing number of cases in the UK."

More now from UK Transport Secretary Grant Shapps, who says there’s nothing in the data to suggest the UK needs to implement its Covid Plan B in the wake of the new coronavirus variant.

Plan B is the government’s winter backup plan for Covid and would see a return to working from home, mandatory mask wearing and vaccine passports.

Shapps says the number of confirmed cases of the new variant is low - none have been identified so far in the UK - and the chances of someone having already brought it back “remain small”.

He says while cases were relatively high, the ratio between cases and hospitalisations and deaths is lower in the UK than in other countries.

He adds that could show the UK is detecting more cases and that our “wall of vaccination and particularly the boosters… is working.”

Singapore is the latest country to place seven nations, including South Africa, on its travel red list.

The country's Ministry of Health says all travellers with recent travel history to Botswana, Eswatini, Lesotho, Mozambique, Namibia, South Africa and Zimbabwe will no longer be allowed to enter into or transit through Singapore, from 23:59 on Saturday.

It adds that it has so far has zero cases of the variant.

Image source, Getty Images