The head of UN Environment Erik Solheim has praised China for its efforts to curb pollution. 

"It's true that big Chinese cities are still polluted, but it's also true the Chinese government has taken the strongest actions to defeat pollution we have ever seen," said Solheim in an interview with CGTN. 

Speaking of the upcoming UN Environmental Assembly in December, he said the UN is going to defeat air, water and soil pollution, and to promote a pollution-free planet. 

The Chinese Minister of Environmental Protection will attend the event, for which the UN Environment Programme held a promotional event in Beijing on Wednesday. 

The theme of this year's event is to create a pollution-free planet. 

This week, China will further promote electric vehicles and buses in major cities and phase out gasoline driven cars. 

"It will be good for China, and it will also drive down the price of these vehicles so that it will be affordable for people on this planet," Solheim said.

Despite the progress China has made in environmental protection, the Chinese Ministry of Environmental Protection recently said the period of severe smog had arrived earlier this year. The average concentration of the PM 2.5 particles in the areas around Beijing, Tianjin and Hebei province increased 5.4 percent in the first half of this year compared with the same time last year. In some cities, the concentration has even gone up by 30 percent.

Solheim commented on China's work on handling smog. 

"First I think the situation is serious. I talked to people lately, everyone says that I want to see the sun, and I don't want to live in such a polluted city. At the same time, the government is dedicated to changing the situation and putting in place good policies, such as electric mobility, phasing out coal. China is the primary driver in the solar revolution of the world. And President Xi is taking the main lead, saying clean water, clean forest is the new goal. So, problems are big, but solutions are coming."