China's top environmental watchdog has reiterated its zero-tolerance attitude to one-size-fits-all approaches in environmental governance and vowed to take more measures to serve high-quality development amid challenges from the external economic environment.

Li Ganjie, minister of ecology and environment, made the remarks at the ministry's two-day annual work conference, which ended on Monday.

"The pollution control campaign yielded key progress. The ecological environment in the country has generally improved," Li said in summarizing progress last year.

Emissions of major pollutants continued to fall last year, and the density of PM 2.5 particulate matter in cities that had yet to see air quality reach the national standard continued to decline, Li said.

The national standard for PM 2.5 concentrations is 35 micrograms per cubic meter of air.

Li said 3,626 violations in 899 county-level areas that are sources of drinking water were rectified in 2019. The ministry also managed to clean up 2,513 black and odorous water bodies in cities above the prefecture level.

The ministry imposed administrative penalties totaling about 11.9 billion yuan ($1.7 billion) in 162,900 cases of environmental violations last year, he added.

Despite the improving environmental governance system and the effective implementation of many reform measures in promoting ecological progress, Li said the situation remains grim for environmental protection work.

"Profound and complex shifts are taking place in both international and domestic environments," he said.

"As (China's) external economic environment tends to be more complicated and grimmer, there are more uncertainties. The situation environment protection work confronts remains grim."

Li demanded his colleagues wage the pollution control fight this year with "resolute confidence to win" and "without relaxing the strength", while better serving high-quality development.

Vowing to resort to more precision and tailor-made measures in accordance with law and regulations, he said the ministry resolutely opposed one-size-fits-all approaches in environmental management.

"Upholding a pragmatic approach, we should make work arrangements and draft planning based on the least favorable situation and win the trust of the people with real achievements," he said.