Cities in Asia and the United States are the biggest emitters of greenhouse gases contributing to climate change, with Shanghai being the most-polluting city, a new data, which combined observations and artificial intelligence, revealed.

Seven states or provinces emit more than 1 billion metric tonnes of greenhouse gases, all of them in China, except Texas, which ranks sixth, news agency AP reported. The data, provided by an organisation co-founded by former US Vice-President Al Gore and released during the United Nations climate talks in Baku, Azerbaijan, revealed.