The flight across the Taiwan Strait is scheduled for July or August next year, Xinhua news agency said, citing the mainland Chinese involved.

"Warming cross-strait relations make the flight possible," the report quoted Du Jin'en, of the mainland's Aero Sports Federation, as saying.

It will be first hot air balloon flight across the 135-kilometer-wide (83-mile) strait, and is expected to take between three and seven hours depending on wind conditions, Xinhua said.

China views Taiwan as a rebel province awaiting reunification, by force if necessary. The two sides split at the end of a civil war in 1949.

Relations between the two sides began to relax after China-friendly Ma Ying-jeou became president of Taiwan in May.