BEIJING (Reuters) – China’s President Xi Jinping told his U.S. counterpart Joe Biden that the issues of Taiwan, democracy, human rights and rights to development are “red lines” for China and not to be challenged, the official state media Xinhua said on Sunday.

Xi warned the United States not to get involved in bilateral disputes over islands and reefs in the South China Sea or “aid or abet the impulsion to make provocations” in that region, it said.

China and United States would roil or even see relations take a setback in rivalry with each other, but could make considerable progress by treating each other as partners and friends, Xi told Biden on the sidelines of the Asia-Pacific Economic forum summit in Peru, according to Xinhua.