The Prime Minister will describe the challenge facing humanity as the “most urgent shared endeavour of our lifetimes”.
He will add: “We are in this together and together we will prevail.”
Monday’s online pledging conference – co-hosted by the UK and eight other countries and organisations – aims to bring in more than £6.6 billion in funding to support the global response to the pandemic.
The UK has pledged to give £388 million in aid funding for research into tests, treatments and vaccines – part of a £744 million commitment to help end the pandemic and support the global economy.
Mr Johnson is expected to say: “To win this battle, we must work together to build an impregnable shield around all our people and that can only be achieved by developing and mass producing a vaccine.
“The more we pull together and share our expertise, the faster our scientists will succeed.
“The race to discover the vaccine to defeat this virus is not a competition between countries but the most urgent shared endeavour of our lifetimes.
“It’s humanity against the virus – we are in this together and together we will prevail.”
Coronavirus has claimed more than 244,000 lives around the world, according to analysis by John Hopkins University.
The Government believes tackling the virus globally is crucial to preventing a second wave reemerging in the UK and it will speed up the creation of vaccines, tests and treatment.
International Development Secretary Anne-Marie Trevelyan said: “It is only by working together that we will prevent future waves of infection and end this pandemic as quickly as possible.
“By strengthening developing countries’ health systems and working to find a vaccine, the UK is playing its part in stopping the global spread of coronavirus to save lives everywhere and protect our NHS.”
Writing in The Independent newspaper on Sunday, the leaders of France, Germany, Italy and Norway and senior EU officials said the outbreak has “caused devastation and pain in all corners of the world”.
They said responding to the “global challenge” requires “bringing together the world’s best – and most prepared – minds to find the vaccines, treatments and therapies we need to make our world healthy again”.
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