New Delhi, March 12 -- China is moving to approve a sweeping law to promote what it calls "ethnic unity," a measure that critics say would further erode the rights of some minority groups as authorities cement a push toward assimilation.

The law, expected to be approved by the country's ceremonial legislature Thursday, is designed to foster "a stronger sense of community among all ethnic groups in the Chinese nation," said Lou Qinjian, a delegate to the National People's Congress who introduced the proposal to the whole body.

The proposed law lays out the need to promote ethnic unity by all government bodies and private enterprises, including local governments and state-affiliated groups like the All-China Women's Federation.

"The peop...