Private equity firm the Blackstone Group is to purchase a 20-percent stake in China National BlueStar (Group) Corporation worth 600 million U.S. dollars, BlueStar's parent company ChemChina announced on Monday.

Antony Leung, former financial secretary of Hong Kong and current chairman of Blackstone Greater China, would join the board of directors of the company, a wholly-owned subsidiary of China National Chemical Corporation (ChemChina), along with Ben Jenkins, a senior managing director of the U.S. firm.

The announcement made by the Chinese company also said the deal was still subject to final approvals from regulators.

Ren Jianxin, chairman of ChemChina, said the company was "excited to have Blackstone as a long term parner," and believed the investment would assist BlueStar to grow and expand, saying Blackstone had "extensive and successful experience in the global chemical industry."

The cooperation between the two was hailed as "a privilege" by Antony Leung with Blackstone, and he said continued economic growth would drive long-term growth in China's chemical sector.

This is the first purchase of stakes in a Chinese mainland company by Blackstone. The last time Blackstone made big news in China was in June when China's state foreign exchange investment company bought three billion yuan worth of shares in the Blackstone Group.

UBS AG acted as the financial advisor to ChemChina, and Merrill Lynch to Blackstone.

The U.S.-based Blackstone Group is a leading global private equity firm with nearly 90 billion dollars of assets under its management. It raised a total of 4.1 billion dollars for its initial public offering in June.

BlueStar is a chief manufacturer of new material and specialty chemical products with annual sales of over 30 billion yuan under ChemChina, the country's leading chemical maker.

The shares of BlueStar's three listed units, BlueStar New Chemical Materials Co., Ltd, BlueStar Cleaning Co., Ltd, and Shenyang Chemical Co., Ltd, were suspended from trading last Thursday.