It's time for us to wrap up today's live coverage of coronavirus in the UK and around the world.

Today's updates were written by Emma Harrison, Kate Whannel, Jennifer Meierhans and Yaroslav Lukov.

The page was edited by Francesca Gillett and Rob Corp.

Image source, Getty Images

Leading public health figures in the US are still trying to wrap their head around what the Omicron coronavirus variant means for the world.

Dr Anthony Fauci, lead infectious diseases expert in the US, said that scientists still need more information on the highly-mutated variant but hospitalisations in South Africa, where Omicron is now the dominant strain, have not risen drastically.

"Thus far, it does not look like there’s a great degree of severity to it," he told CNN on Sunday. “But we have really got to be careful before we make any determinations that it is less severe or it really doesn’t cause any severe illness, comparable to Delta”.

Stephen Hoge, president of Moderna, said there was a "real risk" existing vaccines may not be effective against the new strain.

"What I don't know is how substantial that is," he told ABC News.

The Delta variant continues to be dominant in the US, but Omicron has now been found in at least 17 US states.

Omicron and its infectiousnesspublished at 18:19 Greenwich Mean Time 6 December 2021

18:19 GMT 6 December 2021

James Gallagher
Health and science correspondent, BBC News

Travel restrictions - which slow the influx of new cases - make the biggest difference when there is little Omicron in the country.

Yet scientists have warned Omicron could overtake Delta to become the dominant variant within the next few weeks as it is already spreading here.

The shorter gap between catching the virus and passing it on was used as the justification for pre-departure testing.

But that difference in infectiousness will also accelerate the spread of Omicron that is already here.

All the measures can do is buy time to understand what Omicron is capable of.

It could still take weeks to understand how severe the variant is and what it means for the effectiveness of vaccines.

Sajid Javid tells MPs that the new variant of coronavirus, which was first detected in southern Africa, is now being transmitted in "multiple regions of England". Initially cases of Omicron were linked to international travel.

Former Conservative Prime Minister Theresa May says Omicron appears to be more transmissible than past variants but also appears to lead to less serious disease.

She says "variants will continue to appear year after year" and argues: "We cannot respond to each new variants by stopping and starting our economy which leads to businesses and jobs being lost".

Sajid Javid warns that MPs "shouldn't jump to conclusions on the severity of Omicron" before more data is available.

Conservative MP, former health secretary and current chair of the Commons health committee Jeremy Hunt asks the minister how he is preparing the NHS for the "worst case scenario".

He notes that 10,000 NHS beds are occupied by people waiting for a social care package.

He also expresses concern about delays in cancer diagnosis and treatment.

"When we switch on Omicron care, how do we make sure we don't switch other services off," he asks

Sajid Javid says the NHS has been spending a "significant amount" of time preparing for the winter.

He adds that the government has provided £500m over the winter to help discharge people from hospitals.

Replying to the shadow health secretary, Javid thanks him for his support to the vaccination programme.

"The booster programme itself is steaming ahead at a blistering pace with 2.6 million across the UK were boosted last week and there's some 3.6 million people booked in," he says.

The government is on track to offer all adults a booster jab by the end of January and was already far ahead of any country in Europe.

He estimated there were five million people in the UK that have yet to take up an offer of a jab but 88% of over-12s have had at least one jab.

He says more than 100 test providers have been removed from the government's approved list for showing misleading prices and will "continue to take a tough line on this".

"In terms of rules of course they should apply to everyone regardless of who they are," he says.

Labour's shadow health secretary Wes Streeting responds for the opposition.

He asks when the government will hit its target of administering half a million booster jabs a day.

He also asks when the booster jab will be rolled out to under-40s and what plans there are to encourage people to get fully vaccinated.

"Too many hospital beds are being diverted to those who have chosen not to get the vaccine," he adds.

On testing, he urges the government to tackle "the racket of soaring testing costs and poor provision of quarantine provision".

Finally, he says it is time for the government to "come clean" about the Christmas party held in Downing Street.

"Or does he believe it is one rule for them and another for everybody else?" he asks.

As well as tightening travel restrictions, the health secretary announces a range of measures aimed at "strengthening vital defences here at home".

He says another new treatment has been approved by the UK's medicines regulator the MHRA.

The UK has given 450,000 booster jabs in a single day passing the total of and 20m third doses.

He says 10,000 more paid vaccinators will be recruited and there will be jabs given at 1,500 pharmacy sites along with new hospital hubs and vaccination centres.

"We are doing everything in our power to strengthen our national defences so we will be as prepared as possible for whatever this virus brings."

Javid outlines the UK's plan to test people in the two days before they come to the UK.

Because scientists believe the window between infection and infectiousness may be shorter with Omicron, he says, pre-departure testing may have a greater part to play in identifying new cases before travel.

From 04:00 GMT tomorrow anyone travelling to the UK from countries not on the red list must show a proof of a negative PCR or lateral flow test whether they are vaccinated or not, he says.

This applies to those aged 12 and above and tests must be taken no more than 48 hours before travel.

He stressed these are "temporary measures while we improve our understanding of Omicron", adding that the data will be reviewed and the House of Commons will be updated next week.

Javid now lays out the new measures - which have come into force today - implementing travel restrictions on people coming from Nigeria.

He says 21 Omicron cases in England have been linked to travel from Nigeria, adding that there is "strong invocation" Omicron is present in the country.

Javid says scientists believes the "window between infection and infectiousness may be shorter" for the Omicron variant than Delta.

However, he adds that there is "no complete picture" over whether the Omicron variant causes more severe disease or how it interacts with vaccines.

Image source, ParliamentLive.TV

Sajid Javid begins by telling MPs there have been 261 confirmed cases of Omicron in England, 71 in Scotland and 4 in Wales, bringing the total number of confirmed cases to 336.

This includes cases with no links to international travel, he says.

"We can conclude there is now community transmission across multiple regions in England," he says.

The variant is also in 52 countries, he adds.

Sajid Javid is on his feet to give the House of Commons an update on the latest situation with coronavirus.

MPs will also get the chance to put questions to the health secretary. Stick with us for updates on what he says.

As we reported earlier (see our 10:43 post), a number of European countries have now adopted stricter measures in response to rising Covid infections and deaths as winter approaches.

Here are several infographics showing the latest Covid trends across the continent.

Cases in Austria appear to have fallen recently, after the country returned to full lockdown for anyone not fully vaccinated.

While we're waiting for Javid to speak, let's return to Omicron - which now has 336 confirmed cases in the UK - and the work that's going on to identify new cases.

Swabs from polymerase chain reaction (PCR) tests, which are sent to labs for analysis, can show if the variant causing the infection looks like Omicron, Delta or something else.

Between a third and a half of UK labs - but not all - have the required technology to detect suspected Omicron cases. That means some parts of the country may identify more Omicron cases more quickly.

Confirming that a suspected case is Omicron requires a full genetic analysis, which can take up to a couple of weeks.

Read more in our explainer here.

Image source, Getty Images

Flying to the US soon? There are new measures coming your way.

Starting today, all inbound passengers over two years old are now required to present a negative test result from within 24 hours of their departure time.

The rule will apply regardless of vaccination status or nationality.

The US and several other countries have already banned travel from eight southern African countries, a move that many critics have slammed as "travel apartheid".

Chief medical adviser to the US president, Dr Anthony Fauci, said on Sunday that US officials felt "very badly" about the hardship caused by the travel ban, and were re-evaluating the move "on a daily basis".

Meanwhile, a federal rule that requires passengers on planes, trains and buses to wear face masks has been extended through March.

At least 17 US states have now reported cases of the Omicron variant.

Image source, PA Media

Health Secretary Sajid Javid will shortly be giving MPs an update on Covid in the House of Commons.

He is expected to start from around 17:00 GMT.

We'll bring you all the updates from his statement when it kicks off.

BBC Monitoring
The world through its media

Image source, EPA

Russia has recorded its first two cases of the Omicron variant, a federal watchdog says.

Two people who had already tested positive for Covid upon returning from southern Africa have now been confirmed infected with Omicron, Russian consumer and public health watchdog Rospotrebnadzor says.

Russian authorities have recently tightened rules for those arriving from South Africa and neighbouring countries, introducing compulsory tests at the border as well as a two-week quarantine.

Even before the arrival of the new variant Russia was already enduring a particularly deadly Covid spell, frequently setting new daily death records at more than 1,200.

Russia has confirmed 282,462 Covid-related deaths since the start of the pandemic, Rospotrebnadzor says.

At the same time, Rosstat - Russia's official statistics agency - says more than 537,000 people died in the country between April 2020 and October 2021 after a confirmed or suspected Covid infection.

Rosstat uses broader criteria in its tallying system than Rospotrebnadzor.

The controversy over a Christmas party held at Downing Street during last year's Covid restrictions has "struck a chord with people" who had to sacrifice seeing family and friends at the time, says the journalist who first broke the story.

The Daily Mirror's political editor Pippa Crerar - who first published the story last Tuesday - tells the BBC: "The fact that questions are still being asked almost a week later comes back to the fact that the public are, despite it being a year ago, reminded of what an awful time that was for many of them."

The Covid restrictions operating at the time banned such events - but the government has repeatedly said no rules were broken. Boris Johnson was not at the party.

Crerar says: "I think it's clear that people aren't satisfied with the answers they are getting from ministers."

The prime minister's official spokesman earlier declined to say whether an internal investigation had been carried out, but told reporters: "There was not a party, and Covid rules have been followed at all times."