Taiwan to boost Pratas islands defences as Chinese presence looms

Kuan Bi-ling, head of Taiwan's Ocean Affairs Council, said China was gradually expanding the maritime areas in which it carries out "grey zone harassment" - referring to non-combat operations designed to put pressure on Taiwan such as coastguard patrols.

Since last year, the number of Chinese Government boats, which include the coastguard, has increased around the Pratas, whereas previously activity was concentrated around Taiwan itself and the Kinmen islands, which sit close to the Chinese coast, she added.

"From a political and strategic perspective, we have found that for them, seizing Dongsha would carry considerable strategic significance," Kuan said, using the name both Taiwan and China use for the Pratas.