The UK government has pledged £330 million a year over the next five years to the global Vaccine Alliance (GAVI) to help fund immunisation of 75 million children in the world’s poorest countries.

The funding makes the UK the largest supporter of GAVI, which vaccinates children against deadly diseases such as measles, polio and typhoid, saving millions of lives.

GAVI has so far helped vaccinate more than 760 million children, preventing more than 13 million deaths.

The UK government said that such a vaccination programme was supporting healthcare systems in developing countries so they could cope with rising coronavirus cases.

The International Development Secretary, Anne-Marie Trevelyan, told British MPs: “The coronavirus pandemic shows us now more than ever the vital role vaccines play in protecting us all.

“As coronavirus vaccine trials begin, we need to make sure any successful vaccine will be available to everyone.

“GAVI will be integral to achieving this, so we can protect the UK and the NHS [National Health Service] from future waves of infection.”

Dr Seth Berkley, CEO of GAVI, said an investment in the organisation was “an investment in a safer, healthier world”.

He said that apart from protecting hundreds of millions of children against disease, “it will also help health systems to repair and rebuild after the enormous impact of COVID-19 has subsided”.

“This is our best shield against future pandemics which, as we have seen all too clearly in recent months, do not respect borders,” Dr Berkley added.

He said the money would help GAVI to continue its “work leading international efforts to ensure universal access to a COVID-19 vaccine, as well as to maintain the infrastructure needed to deploy it at scale around the world, which offers our best means of ending this crisis”.

Bill Gates, co-chair of the Bill & Melinda Gates Foundation, said: “When the world beats the COVID-19 pandemic and life returns to normal, GAVI – and the UK’s support of it – will be a major reason why.”

He said that GAVI’s work over the past 20 years had been “incredibly effective, and with this new funding, they’ll be able to continue their work when a COVID vaccine is ready”.

Dr Ngozi Okonjo-Iweala, Chair of the GAVI Board, said the alliance was currently “playing a vital role [in] keeping immunisation programmes going across the world, reducing the chances of there being further global disease outbreaks, as well as helping developing countries respond to the COVID-19 pandemic”.

She added: “As long as there are still pockets of this disease somewhere, everywhere is at risk.”

The UK has been a long-standing donor to GAVI since its formation in 2000, and the funding announcement comes as the government prepares to hold a virtual Global Vaccine Summit on June 4 hosted by Prime Minister Boris Johnson.

It will bring countries together to help raise $7.4 billion for GAVI’s work.