UNITED NATIONS (AFP, REUTERS) - China on Thursday (Jan 7) threatened that the United States would pay a heavy price if its United Nations Ambassador Kelly Craft kept plans announced by the State Department to travel to Taiwan in the coming days.

"The United States will pay a heavy price for its wrong action," a statement from the Chinese mission to the UN said.

"China strongly urges the United States to stop its crazy provocation, stop creating new difficulties for China-US relations and the two countries' cooperation in the United Nations, and stop going further on the wrong path."

China firmly opposes the visit and demands the US cancel its plans, the statement added, reiterating Beijing's One China policy that maintains Taiwan is only a mainland province.

Ms Craft will visit Taiwan from Jan 13 to 15 for meetings with senior Taiwanese counterparts.

"During her trip, the ambassador will reinforce the US government's strong and ongoing support for Taiwan's international space, in accord with the US one-China policy that is guided by the Taiwan Relations Act, the three US-PRC joint communiques, and the Six Assurances to Taiwan," the US mission to the UN said in a statement.

Chinese state news agency Xinhua had also criticised the trip earlier in the day, saying an US ambassador's presence in Taiwan would violate Chinese sovereignty.

Administration officials under President Donald Trump already visited Taiwan last year, despite opposition from Beijing, amid US-Chinese tensions over trade, security and human rights.