WASHINGTON (AP) — The U.S. says new restrictions by Chinese authorities on other countries’ fishermen in the disputed South China Sea are “provocative and potentially dangerous.”

The regulations, which took effect this month, require foreign fishermen to ask China’s permission to operate within most of the vast, strategic waterway.

State Department spokeswoman Jen Psaki said Thursday that the regulations appear to apply to extensive maritime claims for which China has not offered any explanation or basis under international law.

The affected waters cover much of the South China Sea, an area encompassing island groups also claimed by Vietnam, the Philippines and others.

It follows China’s 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.