Keir Starmer has addressed the nation in a pre-recorded broadcast to give his response to the new target for all over 18s to get their booster jab by January.
In the televised speech, the Labour leader said: ministers should have acted sooner in the face of the threat from the fast-spreading Omicron strain.
He urged everyone to "stick to the rules" and get jabbed.
“We may not be certain how dangerous it is but we do know that lives are at risk and again our NHS is at risk of being overwhelmed,” he said.
“If that happens more people will die.
“So we must do everything that we can to protect the NHS.”
He said it would be a “big challenge” to get everyone boosted, but that he was confident the public would rise to meet it.
“Time and time again the British people have risen to the challenge so let’s pull together now and do the right thing once more,” he said.
“At times like this, we must all put the national interest first and play by the rules.
“Of course I understand that sticking to the rules can be inconvenient but stick to the rules we must.
“It would be easy to let the festivities we’ve all been looking forward to, divert us from our national duty.
“Getting jabbed, wearing masks and working from home if we can really will help prevent infections and help prevent the NHS being overwhelmed.”
"Get Britain boosted, protect the NHS, and save lives."
He ended the address by wishing Britians a Happy Chrsitmas.
What did Boris Johnson's announcement say?
The target for giving every adult in England a booster jab has been brought forward by a month over fears of a “tidal wave of Omicron” that could cause “very many deaths”.
Boris Johnson, in a pre-recorded address to the nation on Sunday December 13, said Britain “must urgently reinforce our wall of vaccine protection” as he set a new deadline of jabbing everyone over 18 by the new year.
He said scientists had discovered that being fully vaccinated is “simply not enough” to prevent the spread of the coronavirus mutation and that, without a lightning speed mass booster campaign, the NHS could be overwhelmed.
The announcement comes as the UK Covid alert level was raised to Level 4, up from Level 3, following a rapid increase in the number of Omicron cases being recorded.
READ MORE: UK could exceed one million Omicron variant Covid cases in December
READ MORE: UK Covid Alert Level increased from Level 3 to Level 4 - what does it mean?
Omicron emergency booster national mission
The Prime Minister said: “We’ve already seen hospitalisations doubling in a week in South Africa and we have patients with Omicron here in the UK right now.
“At this point our scientists cannot say that Omicron is less severe.
“And even if that proved to be true we already know it is so much more transmissible that a wave of Omicron through a population that was not boosted would risk a level of hospitalisation that could overwhelm our NHS and lead sadly to very many deaths.
“So we must act now. Today we are launching the Omicron emergency booster national mission, unlike anything we’ve done before in the vaccination programme, to get boosted now.
“A fortnight ago I said we would offer every eligible adult a booster by the end of January.
“Today in light of this Omicron emergency I’m bringing that target forward by a whole month.
“Everyone eligible aged 18 and over in England will have the chance to get their booster before the new year.”
The Prime Minister – whose address was pre-recorded, meaning he spoke to the nation without being flanked by his scientific advisers and without taking questions – said the UK Government would support the devolved administrations to “accelerate” their own rollouts of third jabs.
READ MORE: Omicron variant symptoms - What are the symptoms of the new Covid variant
When can you book your booster?
Every adult over 18 in England who has had a second dose of a vaccine at least three months ago will be able to have their booster from Monday.
The NHS booking system will be open for those under the age of 30 from Wednesday but the Prime Minister said “in some cases you can walk in from tomorrow”.
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