The Great Hall of the People in Beijing used to hear loud applause for leaders announcing ambitious economic plans.

Premier Li Keqiang prepares to deliver the Government Work Report at the opening meeting of the NPC's annual session in Beijing on Thursday, watched by President Xi Jinping. [Photo by Wu Zhiyi / China Daily]

This changed on Thursday, when Premier Li Keqiang earned the biggest applause from the National People's Congress for his pledge of tough environmental protection measures.

In his annual Government Work Report to China's lawmakers at the opening of their 2015 plenary session, the premier called pollution a "blight on people's quality of life and a trouble that weighs on their hearts".

He promised to build a more effective environmental regime in a country plagued by frequent smog and other types of pollution from industrial operations.

The NPC's opening event was attended by nearly 3,000 lawmakers and more than 2,000 political advisers, who will discuss and finalize the overall program for the nation's 2015 social and economic development.

After announcing China's major economic targets for this year — with the GDP growth rate adjusted to 7 percent from 7.5 percent last year — the premier said the nation will cut its use of energy, as measured by energy intensity, by 3.1 percent while reducing the discharge of all key pollutants.

Carbon dioxide intensity will be cut by at least 3.1 percent, reducing both chemical oxygen demand and ammonia nitrogen emissions by about 2 percent, and reducing emissions of sulfur dioxide by around 3 percent and nitrogen oxides by about 5 percent.

Li also pledged to enforce environmental laws and regulations, to crack down on illegal emissions, to ensure heavy penalties are handed out to offenders, and to hold officials who allow illegal emissions accountable for their irresponsible conduct.

Chen Jining, the newly appointed minister of environmental protection, echoed the premier by telling reporters that his main duty is to reinforce the pollution control laws.

Only eight of the 74 major Chinese cities subject to air quality monitoring of PM2.5 met the national standard for clear air last year, according to the Ministry of Environmental Protection.

Li also pledged that the government will promote the use of new-energy vehicles, reduce vehicle exhaust emissions, raise the national fuel quality standard and provide higher-quality gasoline and diesel. All highly polluting vehicles registered before 2005 will be banned from the roads.

Xu Shaoshi, minister of the National Development and Reform Commission, the country's top economic planning body, said energy consumption per unit of GDP value fell by 4.8 percent and carbon intensity by 6.2 percent last year, the best result in terms of energy saving since 2011. China has pledged previously that carbon emissions will peak "around 2030".

Chen Guoying, an NPC deputy and environmental protection director from Hebei, said the province, notorious for its excessive steelmaking capacity and smog, is making its most serious effort to fight pollution.