Mr Johnson reiterated that the goal is to offer every adult an extra dose by the new year when he visited a vaccination centre in London this morning, but there has been confusion over whether the new target, announced last night, means needles in arms by the end of December, or every adult being able to book an appointment by that date.
Doses will be available over the holiday period. Speaking to journalists this morning, Mr Johnson’s official spokesman said: “My understanding is that there will be appointments available on Christmas Day, and obviously the NHS will monitor what the demand is.
“There was, for example last year, the NHS was open for vaccinations on Christmas Day, which we didn’t see a huge demand (for) on Christmas Day.”
With less than three weeks left to the end of the year, the spokesman added: “Should individuals wish to come forward, we will make sure there is capacity.”
Given the speed at which the new Omicron variant is spreading, there have been concerns over whether the reinvigorated booster campaign will be enough to keep the virus at bay.
Mr Johnson repeatedly declined to rule out further rules and confirmed that one patient with Omicron has now died, but said he was confident “people are going to rise” to the challenge.
Speaking to broadcasters, he said: “Throughout the pandemic I’ve been at great pains to stress to the public that we have to watch where the pandemic is going and we take whatever steps are necessary to protect public health.
“We think the steps that we are taking – so Plan B, combined with a hugely ambitious acceleration of the booster campaign, bringing it forward by a month so we offer a booster to every adult by the end of the year – we think that’s the right approach.
“We now want to hit warp speed and we’ll have to attain a pace and a number of daily booster doses that will exceed anything that we’ve done before.
“But I’ve got no doubt at all that we have the people, we have the enthusiasm, we have the fundamental optimism about what we can do, which we’ve learned from the experience of the last 18 months. And I know that people are going to rise to this.”
The vaccination online booking service struggled with demand on Monday morning, seeming to crash for a number of users across the country.
People were urged to try later in the day or tomorrow, and at the same time, lateral flow devices were showing as unable to order from the gov.uk website.
The UK Health Security Agency has said that “due to exceptionally high demand, ordering lateral flow tests on gov.uk has been temporarily suspended to fulfil existing orders”.
They added: “Everyone who needs a lateral flow test can collect test kits – either at their local pharmacy, some community sites and some schools and colleges.”