Government ministers are returning to Egypt to take over climate negotiations at Cop27, providing diplomats with the political backing needed to clinch credible agreements that would help prevent disastrous levels of warming in the coming decades.

The United Nations talks in the Red Sea resort of Sharm El-Sheikh got off to a plodding start and are behind the pace of previous meetings, with three days left before the scheduled close on Friday.

But a small thaw in relations between the US and China at the G20 meeting in Bali has boosted hopes that the world’s top two polluters can help get a deal over the line in Egypt.

US climate envoy John Kerry confirmed on Wednesday that he and his Chinese counterpart Xie Zhenhua had resumed formal talks after they were frozen three months ago by Beijing in retaliation for US House of Representatives speaker Nancy Pelosi’s trip to Taiwan.

Asked what his goal for the outcome of the meeting was, Mr Kerry was cautious, saying: “We’ll have to see, it’s a late start.”

Delegates have been haggling over whether to restate the 2015 Paris accord’s headline goal of limiting global warming to 1.5C and the rules countries set themselves for reducing greenhouse gas emissions.

Officials from developing nations are pushing for rich countries to fulfil pledges of further financial aid for those struggling to cope with global warming.

One significant aspect of that could be payments for “loss and damage” resulting from climate change, which developed countries have long resisted for fear of being held financially liable for the carbon dioxide they have pumped into the atmosphere for decades.

But there has been a softening of positions among some rich nations that now acknowledge some form of payment will be needed.

“Countries that are particularly affected, who themselves bear no blame for the CO2 emissions of industrial nations such as Germany, rightly expect protection against loss and damage from climate change,” German foreign minister Annalena Baerbock said as she departed for Egypt.

She acknowledged that negotiators have “a difficult path” ahead for a substantial agreement.

Geopolitical tensions have been reflected at this year’s talks, with EU delegates walking out of a speech on Tuesday by Russia’s special climate representative, and a small group of Ukrainian and Polish activists briefly disrupting a Russian side event.

Brazilian president-elect Luiz Inacio Lula da Silva received a more enthusiastic welcome at the talks in Egypt. He met Mr Kerry late on Tuesday and was due to hold talks with other leaders, despite not yet being in office.

Brazil’s efforts on climate change are seen as vital because its Amazon rainforest provides a vast carbon sink where emissions can be stored, whereas deforestation would fuel global warming.