China Gas Holdings has formed an alliance with UK-listed Fortune Oil that would merge their natural gas business units in China, Fortune said in a filing to the London Stock Exchange Monday.

Fortune will inject its gas business into China Gas for $400 million in a mix of cash and China Gas shares. Fortune will also have the right to nominate two directors to the board of China Gas, including one executive director and the managing director.

Fortune said its natural gas business was complementary to the assets of China Gas and their combined portfolio would create an enhanced gas supply platform.

The merger would enlarge Fortune's natural gas operations to 200 cities and expand the business scope from city gas to LNG as a transportation fuel.

"This transaction allows Fortune Oil to create one of the largest natural gas operators in China ... We believe there are synergistic benefits from combining the two companies," said Fortune's CEO Tee Kiam Poon.

"Fortune Oil will continue to have access, through its shareholding in China Gas, into the fastest growing natural gas market in the world with an even larger platform."

Fortune has an existing stake in China Gas through China Gas Group, its 50-50 joint venture with China Gas founder Liu Ming Hui. A representative for Fortune said China Gas Group currently owns 18.4% of China Gas.

Fortune's gas division includes a 25% stake in the Liulin coalbed methane block in Shanxi province and gas pipeline infrastructure covering Beijing, Tianjin and Chongqing and seven provinces -- Shanxi, Henan, Hebei, Shandong, Liaoning, Jilin and Hubei. It also operates CNG stations in the transportation sector. The business segment generated $59 million in revenue last year.

Hong Kong-listed China Gas is primarily involved in city gas pipeline and gas distribution services as well as LPG sales to residential, commercial and industrial users in China. The company earlier this year was the target of a failed joint takeover bid by state giant Sinopec and rival ENN Energy.

The deal with Fortune is subject to government approvals, including those from the Anti-Monopoly Bureau of China's Ministry of Commerce and Hong Kong's Takeovers Executive or Takeovers and Mergers Panel.