-USS Ronald Reagan aircraft carrier sails near contested Fiery Cross Reef, with Chinese warships seen nearby

-Military analyst says it's likely to provide an escort for the US House speaker if she proceeds with trip to Taiwan

As tensions mount over US House Speaker Nancy Pelosi's potential trip to Taiwan, the Chinese navy has been monitoring the USS Ronald Reagan aircraft carrier's activities in the South China Sea.

The nuclear-powered warship was cruising about 185km (115 miles) from the contested Fiery Cross Reef in the Spratlys chain on Thursday, according to publicly available satellite images.

Two other vessels - identified by Vietnam-based maritime observer Duan Dang as a Chinese Type 052D destroyer and a Type 054A frigate - were seen 27km and 23km away.