The United States is monitoring reports of Chinese warships docking in Cambodia and has serious concerns about Beijing's plans to have exclusive control over parts of the main naval base there, a State Department spokesperson said on Wednesday.

Radio Free Asia reported on Tuesday that Chinese warships had arrived at Cambodia's Ream Naval Base and cited Cambodian Defense Minister Tea Seiha as saying in a Facebook post on Sunday that this was "in preparation for training" of the Cambodian Navy.

RFA said the warship visit coincided with meetings in Phnom Penh on Monday between Cambodia's leaders and He Weidong, vice chairman of China's Central Military Commission, Beijing's top military command body.