More than 11 billion doses are needed to vaccinate 70% of the global population – a key threshold to ending the acute phase of the Covid-19 pandemic, the UN chief said Thursday.

This will take the largest public health effort in history, the UN Secretary-General António Guterres said while addressing the first International Forum on Covid-19 Vaccine Cooperation in China through a video message.

The global pandemic has already claimed more than 4 million lives. Against this backdrop, Guterres underscored that the world needs a Global Vaccine Plan to at least double vaccine production and ensure equitable distribution, using COVAX as a platform.

"We also need an Emergency Task Force – at the G20 level – to coordinate its implementation," he said.

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Although the remarkable and rapid development of Covid-19 vaccines offers "great hope" that the devastating pandemic can be overcome, everyone must be reached everywhere, "as quickly as possible," the UN chief said.

To double the manufacturing capacity, a much greater sharing of technology and know-how will be needed.

It will also require strengthening and building local production capacities around the world and addressing supply chain bottlenecks, according to the UN chief.

"This is a matter of fairness and justice – but it is also critical to avoid the emergence of further variants that can resist the current vaccines and undermine national vaccination efforts," he said.

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The UN chief welcomed agreements signed last month with the UN-led equitable vaccine distribution initiative, COVAX, for the provision of Chinese-developed Sinopharm and Sinovac shots, saying the deal unlocked potential supplies of more than 500 million doses.

Also, the top UN official described the first meeting of the International Vaccine Forum as "a critical opportunity to bring together countries with vaccine production capacities, pharmaceutical companies and manufacturers to advance global cooperation on vaccines."