China has urged the United States to observe promises it made in the three China-US joint communiques and handle Taiwan-related issues cautiously and properly, after US Secretary of State Rex Tillerson voiced his government's commitment to the one-China policy but also its intentions to keep its commitments to Taiwan.

Foreign Ministry spokesman Lu Kang made the comment on Thursday, saying the one-China principle is the political foundation of China-US ties and is clearly stipulated in the three joint communiques between the two countries.

Tillerson was quoted by Reuters as saying on Wednesday that the Trump administration is committed to the one-China policy but it also intends to keep its commitments to Taiwan.

Lu said that since the Trump administration took office, the US leadership, including President Donald Trump and Tillerson, has "unmistakably expressed" in exchanges with China that the US will uphold the one-China policy.

Also, the US is "very clear" about the fact that the one-China principle is a recognized norm for international relations as well an important prerequisite for developing ties and cooperation with China, the spokesman said.

Tillerson also said on Wednesday that the US is discussing whether the one-China policy is sustainable for the next 50 years.

In response, Lu said on Thursday that the US itself would have to explain what such comments mean exactly, and warned "some people" in Taiwan to discard any "hallucinations".

Lu suggested those people take a look at the past 50 years to understand correctly how things will develop in the next five decades.

"Regardless of whether it is the general trend of the international community, of the development of China-US ties, or of the great rejuvenation of the Chinese nation, I hope they will get an accurate understanding of the future by comparing the past 50 years and today," he said.

Regarding reports that Nigeria, the United Arab Emirates, Bahrain, Jordan and Ecuador have asked Taiwan to rename its representative offices in their countries, Lu said that the Chinese government "speaks highly of these countries' dealings with Taiwan-related issues following the one-China principle".

The reports came shortly after Panama announced the establishments of diplomatic ties with China and severed "diplomatic ties" with Taiwan.

Lu said on Thursday that China welcomes Panamanian students who have been offered scholarships by Taiwan to study in the Chinese mainland in case they face difficulty completing their studies after Panama cut ties with Taiwan.

He said China hopes to provide timely and necessary assistance to these students, and that the country will offer new scholarships to Panamanians every year.