Eswatini has pushed back after Beijing accused some of its politicians of being "kept and fed" by Taipei

China has condemned Eswatini for hosting Taiwanese President Lai Ching-te, accusing the southern African kingdom of giving a platform to "Taiwan independence," in an escalating diplomatic row.

Foreign Ministry spokesman Lin Jian told reporters on Wednesday that Beijing opposes Eswatini's decision to receive Lai, who arrived in the kingdom on Saturday for a three-day visit after Taipei said several African states had revoked overflight permits under Chinese pressure.

"Some politicians in Eswatini are kept and fed by Taiwan and provide space for 'Taiwan independence,' going against the tide of history. China strongly condemns this," Lin said.

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Lin also accused Lai of violating the sovereignty of other countries, saying the Taiwanese leader had "sneaked" into Eswatini by concealing passenger information and later forced his way through foreign airspace after some states denied him access.

He said the trip shows that "Taiwan independence" separatism is "shady business" and "unacceptable to the international community," adding that there is "but one China in the world" and that Taiwan is an "inalienable part" of China.

Taipei rejected Beijing's accusations, saying Lai's visit was lawful and in line with formal diplomatic practice, adding that the travel plan was not disclosed until after he landed for security reasons.

Eswatini's acting government spokeswoman, Thabile Mdluli, described China's remarks as "deeply unfortunate" and said they "fall short" of the standards of respectful diplomacy, Reuters reports.

Africa's last absolute monarchy, formerly Swaziland, is Taiwan's only diplomatic ally in Africa and one of 12 countries worldwide that maintain formal relations with Taipei. China claims Taiwan as part of its own territory and opposes official contact between the island and foreign governments. Taiwan rejects Beijing's sovereignty claim.

The latest row comes as Beijing deepens trade incentives across Africa while excluding Eswatini.

China said on May 1 it expanded zero-tariff treatment to imports from all 53 African countries with which it has diplomatic relations, leaving Eswatini as the only country on the continent outside the scheme.

The policy, first announced by Chinese President Xi Jinping in February, extends duty-free access beyond 33 least-developed African countries to 20 others for two years. China says the tariff plan is intended to boost African exports and narrow trade imbalances.