China has replaced its top liaison official for Hong Kong, signaling Beijing's growing frustration with prodemocracy protests that have dragged on for months.

Luo Huining will take over from Wang Zhimin as the Hong Kong liaison office director, the government said late Saturday in a two-sentence statement that did not elaborate on the changes in the semi-autonomous financial hub.

Luo served as party secretary in the northern province of Shanxi from 2016 until November and became deputy chairman of the financial and economic committee of the National People's Congress in December.