Taiwan's military will strengthen its efforts to stop spying by China despite eased tensions, a media report said Wednesday.

The armed forces are alarmed at China's increased intelligence activities aimed at Taiwan despite fast improving cross-strait ties, the Liberty Times said.

Citing an "authoritative" source, the paper said the military has agreed to reinstate an anti-espionage unit which was abolished 12 years ago.

This was despite a decision to cut the overall size of the armed forces to a record low of 215,000 next year, from the present 275,000.

Defence ministry spokesman David Lo did not confirm the report but told AFP: "In the face of various infiltration and information collection methods conducted by the Chinese communists, all personnel in the military are required to heighten precautions."

Relations have improved markedly since President Ma Ying-jeou of the China-friendly Kuomintang came to power in Taiwan in 2008 on a platform of strengthening trade and tourism links. He was re-elected in January 2012.

But China still regards Taiwan as part of its territory awaiting reunification, by force if necessary, even though the island has ruled itself since the end of a civil war in 1949.

Taiwan has been hit by several spy scandals in recent years.

In April last year a Taiwanese general lured by a honey trap into spying for China was jailed for life, in one of the island's worst espionage cases for half a century.