The move is aimed at "deepening mutual stock market access between the mainland and Hong Kong, and promote the development of both capital markets," the China Securities Regulatory Commission (CSRC) and the Hong Kong Securities and Futures Commission (SFC) said in the joint statement.

The scope of eligible stocks will be expanded for both the Northbound and Southbound trading links, and preparation for the expansion will take about three months, the regulators said.

Specifically, Northbound trading, which allows offshore investors to buy China-listed shares, will include stocks with a market capitalization of 5 billion yuan or above and meet certain liquidity criteria.

The scheme will also include stocks of companies that have issued both A shares and Hong Kong-traded H shares, according to the statement.

In Southbound trading, which allows mainland investors to buy Hong Kong stocks, the scope will be expanded to include stocks of foreign companies with primary listings in Hong Kong which are constituents of Hang Seng Composite Indices.

The proposal will be launched only after the preparation for relevant trading and clearing rules and systems has been completed and all regulatory approvals have been granted, according to the statement.