GENEVA: The Trump administration's decision to cut US development aid will lead to massive setbacks in the global fight against deadly diseases like malaria and HIV, the World Health Organisation (WHO) said on Monday.

"Over the last two decades, the US has been the largest bilateral donor to the fight against malaria, helping to prevent an estimated 2.2 billion cases and 12.7 million deaths," said WHO chief Tedros Adhanom Ghebreyesus in a statement, reported German news agency dpa.

He noted that "severe disruptions to the supply of malaria diagnostics, medicines and insecticide-treated bed nets" have already been observed as a result of the US cuts.

"If disruptions continue, we could see an additional 15 million cases of malaria and 107,000 deaths this year alone, reversing 15 years of progress," he added.

Tedros also noted that the US funding freeze had caused "an immediate stop to services for HIV treatment, testing and prevention in more than 50 countries."

"Disruptions to HIV programmes could undo 20 years of progress, leading to more than 10 million additional cases of HIV and 3 million HIV-related deaths - more than triple the number of deaths last year," the WHO chief added.

Tedros also warned against setbacks in the fight against tuberculosis and measles, saying a global network of over 700 measles and rubella laboratories funded solely by the US "faces imminent shutdown".

US President Donald Trump has ordered drastic cuts at international development agency USAID and other US institutions that support health projects abroad.

--BERNAMA-dpa