The G7 is meeting face to face for the first time since 2019, at a beachside venue in Cornwall, southwest England, after the coronavirus led to the cancellation of last year's summit.
Leaders are to agree on a joint declaration aimed at preventing another pandemic, as they resume wide-ranging talks at their first in-person summit in almost two years.
The group of leading economies - Britain, Canada, France, Germany, Italy, Japan and the United States - are seeking to showcase Western democratic cohesion against a resurgent China and recalcitrant Russia.
The leaders opened the three-day summit Friday with expectations of a pledge to donate one billion vaccine doses to poor countries this year and next - much too slow to end the crisis now, campaigners said.
The G7 this weekend will also tackle climate change, and safeguarding global biodiversity, to lay the groundwork for the UN's pivotal COP26 environmental summit in Scotland in November.
The G7 is expected to finalize the "Carbis Bay Declaration" comprising a series of commitments to prevent a repeat of the devastation wreaked by the coronavirus.
The G7 leaders are also expected to outline more help for developing nations to build up infrastructure, as a counterpoint to the debt-fuelled spending by China in Africa, Asia, and Latin America.