The United Nations Aids chief has warned that a cut to US funding could lead to over six million further deaths worldwide from the disease over the next four years. Winnie Byanyima also said there will be an additional 2,000 new HIV infections each day.

She claimed that the decision to pause foreign aid was already having devastating consequences and urged the White House to reverse the decision. Many HIV treatment and prevention programmes funded by the US have received stop-work orders. This has led to the closure of mother and baby clinics in Africa and severe shortages of life-saving anti-retroviral (ARV) medicines.

Ms Byanima thanked Washington for its previous generosity and humanity and said it was "reasonable" for the US "to want to reduce its funding - over time".

However, she added that the "sudden withdrawal of lifesaving support [was] having a devastating impact".

Stocks of HIV drugs are already running low in a number of countries across the globe, many of them in Africa.

The World Health Organisation (WHO) said Nigeria, Kenya, Lesotho, South Sudan, Burkina Faso, Mali, Haiti and Ukraine could soon run out of HIV drugs after the US funding pause.

Ms Byanyima said she feared a return to the 1990s, when HIV medication was scarcely available in poorer countries, and infections and deaths soared.

The US President Donald Trump announced the pause on foreign aid, for an initial 90 days, on his first day in office in January as part of a review into government spending.

The majority of the US Agency for International Development's (USAID) programmes have since been terminated.

In February, Trump posted on his Truth Social page that USAID's spending "IS TOTALLY UNEXPLAINABLE... CLOSE IT DOWN!"

The United States Agency for International Development (USAID) was set up in the early 1960s to administer humanitarian aid programmes on behalf of the US government.

It employs around 10,000 people, two-thirds of whom work overseas, according to the Congressional Research Service.

It has bases in more than 60 countries and works in dozens of others. However, most of the work on the ground is carried out by other organisations that are contracted and funded by USAID.