Leaders of the G7 leading western economies will on Sunday back a western rival to China’s “belt and road” initiative, in a plan to mobilise billions of dollars to help developing countries tackle climate change.

Joe Biden has been leading calls to offer poor countries a new source of infrastructure finance, providing a “democratic” alternative to Chinese loans, which are seen in the west as a tool to spread Beijing’s influence.

The G7 summit in Cornwall will agree what allies of Boris Johnson, the summit host, call a “green belt and road” plan, with richer countries helping fund schemes that reduce carbon emissions.

Johnson wants to focus on supporting green initiatives and has been wary of presenting the initiative as an “anti-China” move. British officials say they want the G7 to “show what we are for, not who we are against”.

But the White House favours a wider package of infrastructure support and is explicit about wanting to provide a new counterweight to China’s influence.

“We have a slightly narrower focus,” said one British official.

On Saturday G7 leaders held talks to co-ordinate China strategy. “There was broad agreement that we should co-operate with Beijing on things like fighting climate change, compete in areas like global supply chains and contest on issues like human rights,” said one official briefed on the talks.

The “Build Back Better for the World” plan will grant countries improved access to financing for low-carbon projects such as wind farms and railways.

The plan aims to boost climate funding from multilateral development banks as well as the private sector, and was billed as a “Green Marshall Plan” by some officials, but at a smaller scale.

G7 leaders are expected to commit to increase their contributions to international climate finance to meet the pre-existing target of mobilising $100bn a year from rich countries, to help poor countries support green growth.

However one official watching the discussions said: “It was a short on detail on how this would be achieved.”

A senior US official said on Friday: “The United States and many of our partners and friends around the world have long been sceptical about China’s Belt and Road Initiative. 

“We’ve seen the Chinese government demonstrate a lack of transparency, poor environmental and labour standards, and a course of approach that’s left many countries worse off. 

“But until now, we haven’t offered a positive alternative that reflects our values, our standards, and our way of doing business.”

Environmental groups criticised the lack of detail of how the plan would be financed and operate, leading some to warn it was no more than empty promises. 

Climate change is one of the key priorities for G7 leaders at the summit, but leaders are struggling to agree on finance. Only Germany, Canada, Japan and Italy are expected to announce new climate funding in Cornwall. 

The G7 leaders will pledge to phase out petrol and diesel cars, and to shut down all coal plants that do not use emissions-capturing technology as soon as possible. They will also pledge to protect 30 per cent of the planet’s land and ocean by 2030.

With the UK hosting the COP26 climate summit in November, this weekend’s summit in Cornwall is expected to offer a preview of how the world’s largest industrialised democracies will approach the climate crisis in the international arena. 

Several climate groups were unimpressed, saying the Build Back Better plan appeared vague and weak.

“We still don’t know the timeline or the scale of these announcements, and without that, these are just empty promises,” said Catherine Pettengell, interim head of Climate Action Network UK. 

People familiar with the process said the UK was relatively late in trying to pull together its green infrastructure plan. One official watching Saturday’s G7 deliberations said Johnson on one occasion seemed to mix up the names of various schemes.

Johnson said: “The G7 has an unprecedented opportunity to drive a global green industrial revolution, with the potential to transform the way we live.”

All G7 countries have committed to reaching net-zero carbon emissions by 2050, making climate policies an area of broad agreement. But differences over issues such as coal and climate finance donations have nonetheless made for difficult negotiations over the final language of the leaders communique.

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