The first doses are set to be administered on Tuesday, with the National Health Service (NHS) giving top priority to vaccinating the over-80s, frontline healthcare workers and care home staff and residents.
Britain gave emergency use approval for the vaccine developed by Pfizer and BioNTech last week – jumping ahead in the global race to begin the most crucial mass inoculation programme in history.
In total, Britain has ordered 40 million doses. As each person requires two doses, that is enough to vaccinate 20 million people in the country of 67 million.
About 800,000 doses are expected to be available within the first week.