The Taiwanese foreign ministry said it had lodged a "stern protest" after Cameroon designated the island "Taiwan, Province of China" in paperwork issued to the island's delegation before it departed for the March 26-29 event.

Cameroon then granted members of the group a "visa exemption", but the document did not mention their nationality, misspelled some English names and identified almost all of them as female, the ministry said.

The ministry also said in a statement it was clear that the central African country "had no sincere intention of resolving the issue".

China claims Taiwan is part of its sovereign territory and has tried to erase the self-governed island from the international stage by blocking or hindering its access to global forums. It also opposes the designations "Taiwan" or "Republic of China", its official name.

"The one-China principle is the political prerequisite for the Taiwan region of China to participate in the WTO," Chinese foreign ministry spokesman Lin Jian told a regular news briefing in Beijing on Tuesday.

Lin accused Taiwan's ruling party of "engaging in political manipulation under the pretext of attending the meeting".

Taipei called its WTO snub a matter of "national dignity".

"Considering that our delegation members might encounter obstruction if they attempted to enter Cameroon with a document full of incorrect information, and in order to uphold our national dignity, we had no choice but to be absent," the Taiwanese foreign ministry said.

"The Ministry of Foreign Affairs reiterates that our country joined the WTO as a 'separate customs territory' not subordinate to any other member, and that our equal right to participate must not be infringed."

It previously accused Cameroon of "subservience to China".

The WTO declined to comment.

Taiwan joined the WTO in 2002, shortly after China, and its official name at the organisation is the "Separate Customs Territory of Taiwan, Penghu, Kinmen and Matsu (Chinese Taipei)".

The WTO ministerial conference, its highest decision-making body, will take place in Cameroon's capital Yaounde. It is usually held every other year.