China's Taiwan military drills offer spying opportunity for U.S.

China's expanded drills surrounding Taiwan opened a window to gather intelligence for the United States and its allies, Reuters reported.

The four days of intense drills last week - and extended manoeuvres this week - provide the U.S. an opportunity to scrutinise the missiles China would use as well as its command, control and communications systems, regional diplomats and security analysts say.

And on the strategic intelligence front, the exercises have given a clue to China's ability to blockade the island as a prelude or alternative to any invasion, showcasing the firing of ballistic missiles over Taiwan for the first time as well as simulated air and sea attacks on ships on its east coast.

While acknowledging ongoing data gathering, two U.S. military officials have cautioned that the drills are unlikely to offer the type of in-depth intelligence opportunity provided by other manoeuvres beyond the headlines.