Air China Ltd, the nation's biggest international airline, won full control of a unit, raising its stake in Cathay Pacific Airways Ltd and completing a US$2.3 billion shakeup of Hong Kong carriers.

The airline's HK$3.23 billion ($416 million) cash offer for the shares it didn't already own in China National Aviation Co won support from 99 percent of shareholders who voted at a meeting in Hong Kong on December 15, Kong Dong, the unit's chairman, told reporters. The HK$2.80 a share acquisition will almost double Air China's stake in Cathay Pacific to 17.5 percent.

The takeover will complete a wider deal that also included Cathay Pacific increasing its stake in Air China and its purchase of Hong Kong Dragon Airlines Ltd. The deal may help Air China boost its profit as it plans to work with Cathay Pacific on sales and operations.

"Completion of the airline shakeup will reduce internal competition," said Alan Lam, an analyst at Guotai Junan Securities (Hong Kong), told Bloomberg News. "The Hong Kong airlines may also join forces to compete with domestic carriers and to improve their aircraft utility ratio."

Air China will gain a 7.3 percent stake in Cathay Pacific through its acquisition of CNAC, as the unit is known. It bought a 10.2 percent stake in Hong Kong's largest airline in August for HK$5.39 billion. CNAC gained its shares in Cathay Pacific through the sale of its stake in Dragonair to the carrier earlier in the year.

Cathay Pacific spent HK$4.07 billion raising its stake in Air China to 17.5 percent in August. The following month, it completed the HK$8.22 billion purchase of the shares it didn't already own in Dragonair. The transaction added 21 destinations in China to Cathay Pacific's network.