The Hong Kong-listed arm of China's second-largest telecoms carrier Unicom plans to raise up to $11.3 billion by selling shares to its parent firm, the company has announced.

The announcement, in a statement to the Hong Kong stock exchange late Tuesday, comes just two days after China Unicom's Shanghai-listed vehicle confirmed it would sell $11.7 billion worth of shares to a consortium of high-profile investors including Tencent, Baidu and Alibaba.

The latest move is part of a reorganisation linked to the Chinese government's push to overhaul inefficient state-owned enterprises (SOEs) by attracting private capital, the statement said.

Unicom Group was among six SOEs chosen by Beijing last year to pioneer the "mixed-ownership" strategy.

Nearly 6.7 million shares in China Unicom (Hong Kong) will be sold to parent company Unicom BVI at a price of HK$13.24 ($1.70).

Before the announcement, the shares had closed in Hong Kong on Tuesday at HK$12.04. The market was shut Wednesday due to a typhoon.

The statement said the funds raised would be spent mainly on upgrading Unicom's 4G network capabilities and launching its 5G network.