The government has signed a deal with the pharmaceutical firms GlaxoSmithKline (GSK) and Sanofi Pasteur for 60m doses of a potential Covid-19 vaccine.

If the vaccine proves successful, the UK could begin to vaccinate priority groups, such as frontline health and social care workers and those at increased risk from coronavirus, as early as the first half of next year, the Department for Business, Energy and Industrial Strategy said.

Human clinical studies of the vaccine will begin in September followed by a phase 3 study in December.

Ministers have signed deals for four different types of potential vaccines and a total of 250m doses.

The business secretary, Alok Sharma, said: “Our scientists and researchers are racing to find a safe and effective vaccine at a speed and scale never seen before. While this progress is truly remarkable, the fact remains that there are no guarantees.

“In the meantime, it is important that we secure early access to a diverse range of promising vaccine candidates, like GSK and Sanofi, to increase our chances of finding one that works so we can protect the public and save lives.”