BEIJING — China warned today that ties with the U.S. will likely see new complications and the only way to maintain a stable relationship is by respecting each other’s “core interests.”

Foreign Minister Wang Yi’s remarks appeared to underscore that China’s position on Taiwan is non-negotiable, weeks after President-elect Donald Trump suggested he could re-evaluate U.S. policy on Taiwan. It also mirrored Beijing’s relatively measured posture toward the incoming U.S. administration despite signs of growing wariness.

Wang told the Communist Party mouthpiece, the People’s Daily, that China will strive to boost cooperation with the U.S. but he foresaw “new, complicated and uncertain factors affecting bilateral relations” under Trump.

China complained this month after Trump questioned a U.S. policy that since 1979 has recognized Beijing as China’s government and maintains only unofficial relations with Taiwan. Beijing regards the self-governing island as part of China and has long used the “core interest” formulation to signal that any move by Taiwan toward formal independence could be met with military force.

Trump’s comments on Taiwan, combined with his accusations that China is manipulating its currency and threats of imposing hefty tariffs against Chinese imports, have rattled relations.

Trump’s transition team announced Wednesday that Peter Navarro, who has accused China of effectively waging economic war against the United States, would head a trade policy council inside the White House.