With COVID-19 vaccines on the horizon, the planet's poorest must not be trampled as countries scramble to get their hands on them, the World Health Organization said Monday.

WHO director-general Tedros Adhanom Ghebreyesus said the latest batch of promising results from final-phase candidate vaccine trials showed there was light at the end of the "long dark tunnel" of the coronavirus pandemic.

But he said the world had to ensure they were distributed fairly across the globe.

"Every government rightly wants to do everything it can to protect its people," Tedros told a virtual press conference.

"But there is now a real risk that the poorest and most vulnerable will be trampled in the stampede for vaccines."

AstraZeneca and Oxford University said their prospective vaccine had proved on average 70 percent effective at stopping the virus after trying it on 23,000 people, days after tests of two other candidate vaccines suggested they had more than 90 percent effectiveness.

"With the latest positive news from vaccine trials, the light at the end of this long dark tunnel is growing brighter. There is now real hope that vaccines in combination with other tried and tested public health measures, will help to end the pandemic," said Tedros.

"The significance of this scientific achievement cannot be overstated. No vaccines in history have been developed as rapidly as these. The scientific community has set a new standard for vaccine development."

POOLED VACCINES PROJECT

The novel coronavirus has killed nearly 1.39 million people and more than 58.6 million cases have been registered since the outbreak emerged in China last December, according to a tally from official sources compiled by AFP.

Anticipating the huge demand for any approved vaccine, the WHO has helped create the so-called Covax facility to ensure equitable distribution. Tedros said 187 countries were now on board.

The international vaccine procurement pool aims to lay its hands on two billion doses of safe and effective vaccines by the end of next year.

However, it is struggling to raise the funds needed to provide for the 92 low-income countries and other economies that quickly signed up.

Tedros said $4.3 billion was needed immediately to support the mass procurement and delivery of COVID-19 vaccines, tests and treatments, while a further $23.8 billion would be needed in 2021.

"The real question is not whether the world can afford to share COVID-19 vaccines and other tools; it's whether it can afford not to," said Tedros.

Leaders at the virtual G20 summit said Sunday they would "spare no effort" to ensure fair distribution of coronavirus vaccines, but the united front was punctured by Angela Merkel who voiced concern about slow progress.

The German chancellor said she was concerned that no major vaccine agreements had yet been struck for poorer nations, even as rich countries have already bought up huge numbers of doses from pharmaceutical firms.

The summit pledged to support poor countries whose economies have been ravaged by the crisis but offered little detail.