China’s rejection of U.S. and Philippine proposals to regulate countries’ behaviour in the South China Sea signaled tensions are likely to persist in one of the world’s busiest shipping lanes.

At a regional security meeting this weekend, China rebuffed a U.S. proposal for nations involved in disputes to voluntarily avoid actions that could be provocative. The proposal, and a similar measure by the Philippines at the Asean Regional Forum in Myanmar, were aimed at breathing life into stalled talks on drafting a code of conduct.

“They are not going anywhere because the Chinese don’t see any value in it,” said Richard Bitzinger, a senior fellow at the S. Rajaratnam School of International Studies in Singapore. “Their argument is increasingly there is no reason to do this stuff. In their mind it’s a settled issue.”