LONDON (REUTERS) - The ball is in China's court when it comes to making the UN COP26 climate change conference in November a success, Britain's Mr Alok Sharma, the summit's president, said on Sunday (Sept 19).

Mr Sharma, who said he had had "constructive and very frank discussions" during a visit to China earlier this month, said Chinese President Xi Jinping had not yet confirmed whether he would attend the summit.

"In every conversation I had with the Chinese, they were very clear that they want to see COP26 as a success, so the ball is very much in their court," Mr Sharma told Sky News.

China is by far the world's top greenhouse gas polluter, as well as top coal consumer and producer, but also a leading investor in renewable energy.

However, with its giant economy needing vast amounts of energy, China has been heavily criticised for continuing to build coal-fired power stations. Burning coal is the single-largest source of planet-warming carbon dioxide emissions.

The coming week will be a crucial one for climate change diplomacy.

World leaders are returning to the United Nations in New York with a focus on boosting efforts to fight both climate change and the Covid-19 pandemic.

Scientists and the UN have warned that global warming is dangerously close to spiralling out of control.

Major economies are under pressure to pledge deeper emissions cuts, and the UN and Britain also want more ambitious climate finance pledges for poorer nations.

UN Secretary-General Antonio Guterres and British Prime Minister Boris Johnson will start the week with a summit on Monday to try to save the two-week COP26 conference from failure. The meeting kicks off in Glasgow, Scotland, on Oct 31.

"It's time to read the alarm bell," Mr Guterres told Reuters last week. "We are on the verge of the abyss."