Jan. 21 (Bloomberg) -- China Eastern Airlines Corp. said it ``doubted the sincerity'' of an offer from Air China Ltd.'s parent to buy a stake for at least HK$14.9 billion ($1.9 billion), renewing hostility to a deal with its larger rival.

``It's informal and doesn't conform to legal procedures,'' China Eastern said in an e-mailed statement late yesterday. Air China's parent offered to buy as much as 30 percent of the carrier in cash through a Hong Kong-based unit, Shanghai-based China Eastern said in a stock exchange statement today.

A combination with China Eastern would give Air China, the world's largest airline by market value, a hub in Shanghai and a dominant position in the world's second-largest aviation market. China Eastern's management opposes a deal, preferring to revive a combination with Singapore Airlines Ltd. that was vetoed by minority shareholders earlier this month.

China National Aviation Holding Co., Air China's parent, said that a deal would boost the two airlines' combined annual sales by 4 billion yuan, while cutting 1 billion yuan of costs, according to China Eastern. The company also offered to form a cargo venture, China Eastern added.

China Eastern halted its shares from trading in Hong Kong today.

To contact the reporters on this story: Irene Shen in Shanghai at ishen4@bloomberg.net.

Last Updated: January 20, 2008 20:30 EST