The Government has formally asked the regulator to assess the Oxford University and AstraZeneca jab, bringing a coronavirus vaccine rollout in the UK a step closer.

The move “marks a significant first step in getting the vaccine approved for deployment” if it meets safety, efficacy and quality standards, the Department of Health and Social Care (DHSC) said.

It comes a week after the Medicines and Healthcare products Regulatory Agency (MHRA) was formally asked by the Government to assess the Pfizer/BioNTech vaccine.

Health Secretary Matt Hancock said: “We are working tirelessly to be in the best possible position to deploy a vaccine as soon as one is approved by the independent regulator the MHRA.

“We have formally asked the regulator to assess the Oxford/AstraZeneca vaccine, to understand the data and determine whether it meets rigorous safety standards.”

British scientists have defended Oxford University and AstraZeneca after questions were raised about the results of their vaccine trial.

After a surprise result found 90 per cent protection was achieved when people were given a half dose followed by a full dose, AstraZeneca said it will most likely carry out a further global clinical trial to assess the efficacy of the jab.

The pharmaceutical giant has acknowledged the finding was as a result of a dosing error but said it did not expect any new trial to delay regulatory approval in countries including the UK.

US scientists questioned a lack of detail in the trial results published last week, and the scientific head of the US’s Operation Warp Speed – the programme to supply America with vaccines – told US reporters the half-dose regime was only given to people aged 55 and under.

Scientists across the globe are hoping to find vaccines that work in older people – the group who are most at risk from Covid-19.

Helen Fletcher, professor of immunology at London School of Hygiene and Tropical Medicine (LSHTM), said: “It’s not surprising if some manufacturing issues were still being ironed out when they started clinical trials but early stage trials are all about safety and the safety data we have seen has been very robust.”

The Government said it has secured access to 100 million doses of the Oxford/AstraZeneca jab and 40 million of the Pfizer/BioNTech vaccine.

If approved, a vaccine could be rolled out from December, Mr Hancock has said.