Premier Li Keqiang on Friday issued letters of appointment to new members of a key government advisory body, including former World Bank chief economist Justin Yifu Lin.

Observers said the move reflects a commitment by the Chinese leadership to pursue a scientific and democratic approach to policymaking as the nation's reform efforts move forward.

"I hope everyone can go deep in thought, research extensively and reflect the truth, so that government decisions can better respond to the state of the country and people's opinions, match the need for current and long-term development and follow the call of history," Li said at the ceremony held at Zhongnanhai, the central government complex.