The World Health Organisation has called on members of the public to start donating funds to its new foundation.

It comes after Donald Trump threatened to permanently pull US funding from the global health body.

The body said it has set up the WHO Foundation to “broaden its contributor base”.

But when asked whether the WHO Foundation had been set up as a response to the threat, WHO director general Dr Tedros Adhanom Ghebreyesus insisted the infinitive had been in the making for two years.

During WHO’s tri-weekly briefing on Covid-19, Dr Tedros said: “Until now, WHO has been one of the few international organisations which has not received donations from the general public.

“One of the greatest threats to WHO’s success is the fact that less than 20% of our budget comes in the form of flexible assessed contributions from Member States, while over 80% is voluntary contributions, which are usually tightly earmarked for specific programmes.

“In effect, that means WHO has little discretion over the way it spends its funds.”

He added: “But for WHO to fulfil its mission and mandate, there is a clear need to broaden our donor base, and to improve both the quantity and quality of funding we receive – meaning more flexibility.

“Since February 2018 we have been hard at work supporting the establishment of the WHO Foundation and today it gives us enormous pleasure to launch it officially.

“This is a historic step for WHO, as an integral part of our resource mobilisation strategy to broaden the contributor base.”

It comes after the US has been heavily critical of the organisation in its Covid-19 response.

The US health secretary made scathing remarks about WHO during the World Health Assembly earlier this month.

Alex Azar, said: “WHO must change and it must become far more transparent and far more accountable.”

Then on May 19, Mr Trump posted a letter on Twitter, in which he wrote: “If the World Health Organisation does not commit to major substantive improvements within the next 30 days, I will make my temporary freeze of United States funding to the World Health Organisation permanent and reconsider our membership in the organisation.”

The WHO Foundation is a “independent grant-making entity”, WHO later said in a press release.

The foundation, based in Geneva, will support WHO’s efforts to address the most “pressing global health challenges”.

The briefing also touched on contact tracing, with Dr Mike Ryan, executive director of WHO’s health emergencies programme, saying that the Southern Hemisphere is “teaching” the North on the issue.

“There’s sort of a perception that all technology, and all knowledge moves from North to South on this planet,” he said.

“In fact, when we look at something as fundamental to public health, and to stopping epidemics, as contact tracing, in fact, I think the South is teaching the North.

“Or the North is rediscovering just how important core public health infrastructure, workforce, case finding contact tracing, simple quarantine measures, are and how central these are to stopping new respiratory viruses for which we don’t have treatment or vaccines.”

Meanwhile, he touched on research on T cell response – part of the body’s immune system – to the virus, which “gives us hope that we’re getting the kinds of immune responses that may be helpful for long term protection”.

Dr Ryan said: “There is certainly some evidence with regard to T cells that if you have a previous coronavirus infection, you may be able to mount a more rapid response to Covid-19.

“But there is no empirical evidence that previous coronavirus infections protect you from infection with Covid-19, the jury is still very much out on that.

“But it is interesting to note that, at least in some of the studies, that if we’re getting a more broad-based T cell response there’s more hope then for vaccines and others producing a more long-term immune response.

“So for me, this information is very important. It gives us hope that we’re getting the kinds of immune responses that may be helpful for long-term protection and may also mean that vaccines have a broader protection.”