The World Health Organization on Wednesday voiced concerns over news reports that the United States government has bought almost all the stocks of key COVID-19 drug remdesivir.

The US administration has bought up virtually all the stocks for the next three months of one of the two drugs proven to work against COVID-19, causing alarm among experts and campaigners, the Guardian newspaper reported.

Mike Ryan, executive director of WHO Health Emergencies Program, said the WHO is aware of media reports about procurement of the remdesivir stock and is working with colleagues and partners in the COVID-19 Tools Accelerator program to verify the reports.

"Obviously there are many people around the world who are very sick with this disease. And we want to ensure that everybody has access to the necessary lifesaving interventions," Ryan told a virtual news briefing from Geneva.

He reiterated the WHO's pledge, saying "we are fully committed as an organization with our partners to equitable access to lifesaving interventions".

When asked if the US had made a pledge to make sure COVID-19 vaccines are global public goods, Ryan said it was a question for the US government.

China and several other countries have pledged to make vaccines global public goods once their development proves successful.

US ties with the WHO

US President Donald Trump announced in May to terminate relations with the WHO and also cut US funding to the global health body.

Talking about the current relationship between WHO and the US, Ryan said he can only speak to the technical collaboration. "Certainly we are grateful to continue to engage with our technical counterparts in the United States in all matters related to science and public health," he said.

WHO Director-General Tedros Adhanom Ghebreyesus said: "We are in contact. We are still discussing. There is collaboration on many issues."

Remdesivir, the first drug approved by licensing authorities in the US to treat COVID-19, is made by Gilead and has been shown to help people recover faster.

The first 140,000 doses, supplied to drug trials around the world, have been used up. The US government has now bought more than 500,000 doses, which is all of Gilead's production for July and 90 percent of August and September.

"President Trump has struck an amazing deal to ensure Americans have access to the first authorized therapeutic for COVID-19," said US Health and Human Services Secretary Alex Azar.

"To the extent possible, we want to ensure that any American patient who needs remdesivir can get it," he said.

COVID-19 cases in the US are spiraling out of control. The US had recorded more than 2.6 million cases and 127,000 deaths as of Thursday, according to the WHO.

The Guardian contributed to this story