A spokesman from the Chinese mainland strongly opposed any attempts by Taiwan leader Lai Ching-te to "transit" through the United States for any reason or in any form.

Lai is reportedly planning a "stopover" in New York and Texas on his way to Paraguay, Guatemala and Belize in South America, Taiwan media reported.

Chen Binhua, a spokesman for the State Council Taiwan Affairs Office, warned the Lai administration on Wednesday that their attempts to seek separation with US support are futile and destined to fail.

The US should adhere to the one-China principle and the provisions of the three Sino-US joint communiques, handle the Taiwan question with extreme caution and refrain from sending any erroneous signals to "pro-independence" forces in Taiwan, he said.

Foreign Ministry spokesman Lin Jian on Tuesday urged Paraguay to reject being manipulated and used by "Taiwan independence" forces after Paraguayan President Santiago Pena said that the country is preparing to receive Lai next month.

There is a widely shared view among people from various sectors across Latin American countries whose people have visited China in recent years — as well as some in Paraguay — that Paraguay needs to stop being an outlier of the international community and recognize the one-China principle, Lin said.

He also expressed hope that relevant Latin American and Caribbean countries will see the prevailing trend, act prudently on Taiwan-related issues and join the big family of China-LAC friendship and cooperation soon.

Lai's reported "transit" through the US coincided with the indefinite postponement of his fifth lecture on "diplomacy", part of a series of 10 talks on uniting the island.

Zhu Songling, a professor at the Institute of Taiwan Studies at Beijing Union University, said the arrangement was far from accidental; rather, it was a deliberate move by Taiwan's ruling Democratic Progressive Party to divert public attention during internal and external challenges.

After assessing their polling numbers, the DPP found that the first four lectures, aimed at gauging support ahead of the recall vote on July 26 on the opposition "lawmakers", were poorly received, with online viewership gradually decreasing to several thousands, Zhu said.

Lai was unable to deliver his lecture on "diplomacy" adequately because he had made no achievements in "foreign affairs", with a diminishing number of "diplomatic allies" and the waning relevance of Taiwan's "Indo-Pacific partners "showcasing the bankruptcy of his "foreign policy", he said.

The DPP was hasty to leak information about the "transit "through the media to cover up his failed lecture series, though the specific arrangements for his trip have not been fully agreed upon by the US, Zhu said, adding that "Ironically, Taiwan is just a pawn, following the US's needs."

Chen, from the Taiwan Affairs Office, said Lai's "10 lectures on unity" are a patchwork of fallacious separatist rhetoric full of lies, and they have deliberately distorted history in an attempt to incite cross-Strait confrontation.

The lectures "fully prove that Lai is a thorough destroyer of peace and an out-and-out warmonger", he said, warning that any force or move to split the mainland will be met with a resolute blow from all the Chinese people.