Taiwan has started using unmanned surveillance aircraft to spy on China to reduce the risk to its pilots from an increased deployment of Chinese missiles, media reported Sunday.

The army in March commissioned a fleet of 32 unmanned aerial vehicles, or drones, developed by the military-run Chung Shan Institute of Science and Technology.

Initially the drones, based in the eastern county of Taitung, were watching airspace in the east and south but lately they had extended their range to the Taiwan Strait, the Liberty Times said.

"Now they can effectively monitor China's military movements in the southeastern coastal area," an unnamed senior officer at the defence ministry was quoted as saying.

The paper said the operation has attracted interest from the United States which has been using the sophisticated high-altitude Global Hawk drone to collect military intelligence on China.

The US raised the topic during a recent military exchange programme with Taiwan, it said.

Taiwan's defence ministry declined to comment on the report.

Tensions across the Taiwan Strait have eased since President Ma Ying-jeou's China-friendly administration came to power in 2008 on a platform of strengthening trade and tourism links. He was re-elected in January 2012.

But Beijing has still not ruled out the use of force against the island should it declare independence, even though the two sides have been ruled separately since their split in 1949 at the end of a civil war.