China rejected the core of President Joe Biden’s message to Chinese President Xi Jinping about U.S. policy regarding Taiwan, condemning the federal law that underpins U.S.-Taiwan relations as an “illegal” document.

“The so-called ‘Taiwan Relations Act’ cited by the U.S. side gravely violates the one-China principle and the three China-US Joint Communiqués and essentially places domestic law above international obligations,” said Chinese foreign ministry spokesman Zhao Lijian. “It is illegal, null and void.”