China International Capital Corp (CICC), the country's top domestic investment bank, has filed for an initial public offering in Hong Kong that could be worth up to $1 billion, people with direct knowledge of the plans said.

The filing sets the ball rolling for a flotation expected to take place as early as September, Thomson Reuters publication IFR reported.

A Beijing-based spokeswoman for CICC declined to comment.

CICC itself and ABC International are leading the offering. The company has as its majority shareholder Central Huijin Investment Ltd, a unit of China's $747 billion sovereign wealth fund. Other shareholders include Singapore's sovereign wealth fund GIC Ltd and private equity firms TPG Capital Management LP and KKR & Co.