US President Joe Biden will use his first big presidential moment on the global stage at Friday’s Group of Seven (G7) meeting of world leaders to announce that the US will soon release $4 billion for an international effort to bolster the purchase and distribution of coronavirus vaccines to poor nations, White House officials said. Mr Biden will also encourage G7 partners to make good on their pledges to Covax, a World Health Organisation initiative focused on improving access to vaccines, according to a senior administration official. Former president Donald Trump declined to participate in the Covax initiative because of its ties to the WHO, the Geneva-based agency that Mr Trump accused of covering up China's slip-ups when handling the virus at the start of the public health crisis. Mr Trump pulled the US out of the WHO, but Mr Biden moved quickly after his inauguration last month to rejoin and confirmed that the US would contribute to Covax. The $4 billion in US funding was approved by Congress in December and will be distributed through 2022. The US is committed to working through Covax to ensure "equitable distribution of vaccines and funding globally", White House press secretary Jen Psaki said on Thursday. It remains to be seen how G7 allies will take Mr Biden’s calls for greater international co-operation on vaccine distribution, given that the US refused to take part in the initiative under Mr Trump and that there are growing calls for the Biden administration to distribute some US-manufactured vaccine supplies overseas. French President Emmanuel Macron, in an interview on Thursday with <em>The Financial Times</em>, called on the US and European nations to allocate up to 5 per cent of current vaccine supplies to developing countries – the kind of vaccine diplomacy China and Russia have begun to engage in. This week, UN Secretary General Antonio Guterres sharply criticised the “wildly uneven and unfair” distribution of Covid-19 vaccines, noting that 10 countries have administered 75 per cent of all vaccinations. Last month, Canadian Prime Minister Justin Trudeau raised with Mr Biden the prospect of Canada receiving the vaccine from pharmaceutical company Pfizer's facility in Kalamazoo, Michigan, according to a senior Canadian government official, who spoke to the Associated Press. Canada has received its doses of the Pfizer-BioNTech vaccine from a company facility in Puurs, Belgium, and has experienced disruptions in supply. But Mr Biden, who announced last week that the US will have enough supply of the vaccine by the end of the summer to inoculate 300 million people, is focused for now on making sure every American is inoculated, administration officials said. The president, in his first national security memorandum last month, called for his administration to develop a framework to donate surplus vaccines once there is a sufficient supply in the US. The Covax programme has already missed its own goal of beginning coronavirus vaccinations in poor countries at the same time that vaccine distribution began in rich countries. WHO says Covax needs $5 billion in 2021. Mr Guterres on Wednesday said that 130 countries have not received a single dose of the vaccine and declared that “at this critical moment, vaccine equity is the biggest moral test before the global community". The Group of Seven industrialised nations are the US, Germany, Japan, Britain, France, Canada and Italy. Friday’s meeting of the G7, the first of Mr Biden’s presidency, is being held online. In addition to discussing vaccine distribution, Mr Biden plans to use the meeting to discuss G7 countries' collective competitiveness and the economic challenges posed by China, according to the White House. Mr Biden is also scheduled to address the Munich Security Conference on Friday before travelling to Michigan to visit Pfizer's vaccine manufacturing facility.