Chinese Premier Li Keqiang speaks at a press conference after the closing meeting of the second annual session of China's 12th National People's Congress (NPC) at the Great Hall of the People in Beijing, capital of China, March 13, 2014. (Xinhua/Chen Jianli)

China needs both tough measures and tough regulations to fight pollution, Premier Li Keqiang said Thursday.

Li made the remarks at a press conference shortly after the conclusion of this year's parliamentary session.

Polluters, which harm both nature and human health, will be severely punished, said Li, when responding to a question about smog that frequently blanketed Beijing and some other major cities since winter.

Watchdogs which turn a blind eye to polluting activities and fail to perform their duties will be held accountable, Li added.

"To declare a war on smog doesn't mean we are declaring a war on nature. Rather, we are going to declare a war on our own inefficient and unsustainable model of growth and way of life," he said.

Last year, the State Council issued a ten-point action plan on the prevention and control of air pollution.

China now conducts PM 2.5 monitoring in 161 cities across the country, the most extensive scale among all the developing countries, according to the premier.

China also set a 3.9 percent reduction target for cutting energy intensity this year on top of a 3.7 percent reduction it achieved last year, which is equivalent to cutting coal burning by 22 million tonnes, said Li.

Li admitted there are complex causes for smog and to tackle this problem takes time.

Li called for the government, businesses and every individual of society to act together and make consistent efforts to win the tough battle against smog.