The country's largest private low-cost carrier is offering free round-trip tickets between Shanghai's Pudong airport and Japan's Saga prefecture, a rural area in southern Japan near the city of Fukuoka, until December 20, airline spokesman Zhang Wuan said.

Spring Airlines' flights to Saga, which run three times a week, are now more than half empty compared with 90 percent occupancy before the islands dispute escalated.

Violent protests and calls for boycotts of Japanese products broke out across China in mid-September after Japan bought two of the East China Sea islands, known as the Diaoyu in Chinese and the Senkaku in Japanese, from their private owners.

The offer of free tickets comes after a Saga official visited Spring Airlines in Shanghai, expressing hope that the route would continue with the local Saga government's support, Zhang said. He declined to comment on what support is being offered.

A round-trip Spring Airlines ticket on the Pudong-Saga route can cost from 239 to 3,000 yuan, depending in part on the promotions on offer, while passengers will typically pay an additional 1,030 yuan in tax and surcharges to cover fuel and other costs.

The deal means customers would only pay tax and surcharges and the same offer is set to be extended to another Japan route, between Shanghai and Kagawa, on the Japanese island of Shikoku, Zhang said.

The islands row has also forced Spring Airlines, like other Chinese rivals, to cut the number of flights to Japan.

It has cancelled chartered flights to Tottori in western Japan and cut a total of nine flights from Shanghai to the Tokyo area between October and December. Occupancy on flights to Tokyo has fallen more than 20 percent.

China Eastern Airlines (600115.SS) (0670.HK) has also said it would delay the launch of a new route between Shanghai and Sendai, which was scheduled to start on October18, due to insufficient passenger demand.

China Eastern, one of the country's top three airlines, reported an 18 percent fall in international passenger traffic for September from August, partly due to weakening demand for flights to Japan. (Reporting by Alison Leung; Editing by Edwina Gibbs)

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