China Eastern Airlines Corp. Ltd. and Juneyao Airlines Co, two leading Shanghai-based airlines, have completed their formation of a strategic alliance, including an equity tie-up, creating a dominant force in the nation’s financial hub, said Caixin.

China Eastern. and Juneyao first announced their plans to form the alliance last year, and since then each has taken a major stake in the other. The privately-owned Juneyao now holds about 10% of China Eastern, one of three major state-run airlines that formed during the early reform era from the breakup of China’s former aviation authority.

Both China Eastern and Juneyao issued separate Friday statements on finalization of the alliance, with neither specifying China Eastern’s stake of Juneyao. Local media reports based on an event to announce the development quoted officials saying China Eastern now holds 15% of Juneyao.

The tie-up will create a clear market leader in Shanghai by combining China Eastern’s 46.3% of the market with Juneyao’s No. 3 position at 9.7%, said Lin Zhijie, an aviation expert based in the southern city of Xiamen.