"Good environmental law only gets you halfway there. It needs to be implemented," Pan told Xinhua in an interview.

Calling the new law "the most powerful legislation in the environmental category", the vice minister said it could still fail without ironclad enforcement.

Pan's remarks came days after the National People's Congress (NPC) Standing Committee approved sweeping revisions to the law with tough penalties for polluters.

After two years of discussion, the revision expands the law to 70 articles from 47, enshrining environmental protection as the government's overriding priority, with specific articles and provisions on smog.

Pan acknowledged that China faces tough environmental problems. Legislation on air, water and soil pollution are included in the NPC Standing Committee's five-year legislation plan.