The United Kingdom says half of the country’s adults have received at least one dose of COVID-19 vaccine.

The National Health Service has put shots in the arms of 26.9 million people, or 51% of the adult population, according to the latest government statistics.

The N.H.S. passed the halfway point on Friday by delivering 589,689 doses.

Health Secretary Matt Hancock said Saturday that’s the highest daily total since the mass vaccination program began in early December.

The celebration comes amid growing concerns about the failure of wealthy countries to share scarce vaccine supplies with developing nations.

The director of a London-based health policy think-tank says while Britain should be proud of the success of its vaccination drive, it’s time to start thinking about the rest of the world.

Dr. Jeremy Farrar, director of Wellcome, says the country has the rights to enough doses to vaccinate its entire population twice.

He says ensuring the world is vaccinated is a scientific and economic imperative; “Science has given us the exit strategy, but it will only work if its benefits can reach the maximum number of people around the world.”