The Duke and Duchess of Sussex have written an open letter to G20 leaders claiming promises of vaccine donations from nations are not reaching the globe’s most vulnerable.

On the eve of the G20 summit, Harry and Meghan said access to the Covid-19 vaccine was a “fundamental human right” in the letter also written with WHO director-general, Dr Tedros Adhanom Ghebreyesus.

Leaders from the world’s richest nations are meeting in Rome this weekend.

Environmental issues expected to be high on the G20 agenda, with the UN climate change Cop26 summit opening on Sunday, but the recovery from the pandemic is also likely to be discussed.

In their letter, the trio said: “When the leaders of the world’s wealthiest nations met at the G7 Summit in June, they collectively announced that one billion doses of Covid-19 vaccines would be sent to low- and low-and-middle-income countries to help vaccinate the world.

“Pharmaceutical companies have pledged almost the same.

“Yet, as several nations still don’t even have enough vaccines for their own health workers, the world is left asking, where are the doses?”

The duke and duchess have already taken part in a number of events to highlight the issue of vaccine equity.

In May, they wrote an open letter to the chief executives of pharmaceutical companies like Pfizer, Moderna and AstraZeneca urging them to redouble their support for the UN-sponsored Covax programme.

Covax was set up last year in a bid to establish fair access to the vaccines for poor and rich nations but huge discrepancies have emerged.

Speaking at a Global Citizen event in New York’s Central Park last month, Harry called on pharmaceutical companies to waive their intellectual property rights on Covid vaccines as the pandemic was becoming a “human rights crisis”.

The letter added: “G20 leaders have the power to accelerate long-promised donations and to commit to breaking the hold that manufacturing countries and pharmaceutical companies currently have over access to the vaccines and how they’re made.

“These are public vaccines. Many of the people you represent paid for the research and development of these vaccines. You can join us in saying that access to the vaccine is a fundamental human right.”

The open document concluded: “There are many crises that you – the stewards of our planet – must grapple with this weekend: the climate emergency, the state of our global economy, a recommitment to multilateralism.

“Yet, in many ways, making headway on these priorities depends on whether we can beat this pandemic.”