China has denounced the Philippines for using the deployment of the Typhon intermediate-range U.S. missiles system as a bargaining chip on the South China Sea issue. It warns that such actions endanger regional peace and stability. Yan Yan, director of the Research Center for Oceans Law and Policy at the National Institute for South China Sea Studies, says the U.S. deployment of an intermediate-range ballistic missile (IRBM) in the Philippines undermines China's strategic security environment.