The U.S. is criticizing Chinese plans for a military garrison on an island in the contested South China Sea

Some senators see Beijing's move as provocative and a possible violation of international law.

State Department spokeswoman Victoria Nuland says the U.S. is pressing all countries in the region to work on a code of conduct for the South China Sea.

China on Tuesday declared a new municipality on tiny Yongxing island — a move that's opposed by Vietnam and the Philippines.

Nuland says the U.S. is concerned about such "unilateral moves" and wants to see "all of these issues resolved at the table."