China says it's beefing up its police powers in the disputed South China Sea and requiring foreign fishermen to ask Beijing's permission to operate within about two-thirds of the vast, strategic waterway.

The rules take effect this month and are part of a broadening campaign by Beijing to enforce its territorial claims. They come on the heels of the late November announcement of a new air defense zone requiring foreign planes to notify Beijing of flights over a huge swath of the East China Sea, where China is locked in a bitter territorial dispute with Japan.

The steps add to concerns that President Xi Jinping's push to assert China's role as a regional power could spark a confrontation with neighbors.