China will strengthen efforts to fight corruption and severely punish officials who do not carry out their responsibilities, Premier Li Keqiang said on Sunday.

"Government officials should use their position to better serve the public rather than abuse their power for personal benefit," the premier said at a briefing for domestic and foreign reporters at the close of the third session of the 12th National People's Congress, the country's top legislature.

"We will seriously investigate those officials who are involved in misconduct or are reluctant to perform their duties," Li said.

Fighting corruption and maintaining clean government remain top priorities for the authorities, he said.

Since November 2012, when the new leadership took office, China has rolled out major measures to fight corruption. Corrupt officials have been placed under investigation in line with the law and the measures have won wide public support.

"It's more than necessary to establish a mechanism to combat corruption," the premier said. "We will govern the country according to the law, and no one is above the law."

China will also speed up reforms to break the institutional obstacles and streamline authority, he said.

The government will enhance supervision of officials to prevent them from abusing their power, and eliminate corruption at its roots, he said.

To date, 63 high-ranking "tigers", including former security chief Zhou Yongkang and former Central Military Commission vice-chairman Xu Caihou, have been placed under investigation for "serious discipline violation."

Of the 63 investigated, 28 officials including Zhou have been transferred to the prosecuting departments.