The government has secured an additional two million doses of the Moderna COVID-19 vaccine, which trials suggest has a 95% effectiveness.
The announcement came as the government appointed a minister, Nadhim Zahawi, responsible for the national deployment of the jabs.
The total number of Moderna vaccine doses on order from the US pharmaceutical company is now seven million – enough for 3.5 million people in the UK.
Doses of the jab could begin in the Spring, but it has yet to be approved by the Medicines and Healthcare products Regulatory Agency (MHRA).
The Oxford and AstraZeneca jab could be rolled out within weeks if approved by the MHRA, with the UK having close to 100 million doses on order.
There are also 40 million doses of the Pfizer and BioNTech vaccine on order, which has also been shown to be around 95% effective.
Mr Zahawi, who is also a business minister, said he was “delighted” to be in charge of the vaccine rollout when it happens.
“A big responsibility & a big operational challenge but absolutely committed to making sure we can roll out vaccines quickly – saving lives and livelihoods,” he tweeted.
Kate Bingham, who chairs the government’s Vaccine Taskforce, said: “Since its inception in June, one of the most important stated aims of the Vaccines Taskforce has been to secure access to the most promising vaccines across a broad range of technologies – thereby increasing the chances of having a safe and effective prevention as soon as possible against COVID-19.
“Moderna’s vaccine was an important addition to our portfolio and securing an additional two million doses further adds to the protection we can provide to the public to end the pandemic.”
Health Secretary Matt Hancock said: “Every week, we are getting more positive news about the range of vaccines in development, and thanks to the work of our taskforce the UK has pre-ordered more hundreds of millions of doses from those companies most advanced in their work.
“With a wide range of vaccine candidates in our portfolio, we stand ready to deploy a vaccine should they receive approval from our medicines regulator, starting with those who will benefit most.”