BEIJING: China expanded its coal-to-gas and coal-to-electricity projects to 35 cities in 2018 from 12 cities the previous year, China's environment minister, Li Ganjie, said on Monday, as the world's second-largest economy stepped up its fight against smog.

Li told journalists at a press conference on the sidelines of China's annual parliament meeting that 4.8 million households switched to natural gas and electricity from coal for heating last year.

That was up from 4 million households that were switched in 2017, said Li.