Taiwan and China traded accusations Monday over a physical clash between their diplomats at a reception in Fiji -- with Beijing revealing that a cake helped fuel the dust-up.

Taipei accused two Chinese officials of gatecrashing an event at the luxurious Grand Pacific Hotel in the Fijian capital Suva on October 8 and assaulting an employee.

Taiwan's foreign ministry said its trade office -- its de facto embassy -- was hosting a party for 100 distinguished guests to celebrate Taiwan's National Day.

They claim the two Chinese officials began taking pictures of guests and when asked to leave assaulted an official, putting him in hospital.

"We strongly condemn the actions by the Chinese embassy in Fiji staff for seriously violating the rule of law and civilised code of conduct," Taiwan foreign ministry spokeswoman Joanne Ou said.

China gave a different version of events.

Beijing's embassy in Fiji confirmed its officials were in a "public area outside the function venue" on unspecified "official duties" on the day of the incident.

But it claimed the Taiwanese mission's staff "acted provocatively" and caused "injuries and damage to one Chinese diplomat".

In a briefing on Monday, China's foreign ministry revealed its officials were aware of details from inside the function, including a cake emblazoned with Taiwan's flag.

"A false national flag was openly displayed at the scene, the cake was also marked with a false national flag," spokesman Zhao Lijian told reporters.

Taipei said the Chinese diplomats were taken away by the police and "falsely claimed" that they had been attacked.

Both sides said they had asked the Fijian police and other island authorities to investigate.

A Fiji police spokeswoman told AFP the probe was ongoing and officers were working with the Pacific nation's foreign affairs ministry. She declined to provide further details.

Fiji's foreign ministry did not respond to a request for comment.

The Taiwanese flag is raised at the Presidential Office in Taipei to mark National Day. Just 15 countries recognise Taiwan, mostly in the Pacific and Latin America
The Taiwanese flag is raised at the Presidential Office in Taipei to mark National Day. Just 15 countries recognise Taiwan, mostly in the Pacific and Latin America AFP / Sam Yeh

China regards democratic Taiwan as a rebel province and has vowed to one day seize the self-ruled island.

The altercation in Fiji comes at a time of high tension between the two sides, with Beijing ramping up diplomatic and military pressure since the 2016 election of Taiwanese President Tsai Ing-wen.

Tsai hails from a party that sees Taiwan as a de facto sovereign nation and not part of "one China".

A senior White House official last week urged her government to build up military capabilities to protect against a possible invasion by China, and the tempo of military activity in the area around Taiwan has increased markedly.

Taiwan's defence depends on whether the US would come to its assistance.

That deliberately ambiguous commitment has been further called into question by President Donald Trump's "America First" doctrine and his on-again-off-again affection for Chinese leader Xi Jinping.

However, Trump has approved some big ticket arms sales to Taiwan.

Chinese diplomats have in recent years become more aggressive in pursuing Beijing's interests abroad, a tactic that has been dubbed "wolf warrior diplomacy".

On Monday, Taiwan's ruling Democratic Progressive Party said: "China's 'wolf warrior diplomacy' is in fact 'hooligan diplomacy'".

Beijing has successfully poached seven of Taiwan's diplomatic allies since 2016, leaving only 15 countries in the world that officially recognise the island.

Most are small Pacific and Latin American nations.

Fiji has long been a staunch China ally and was the first Pacific island nation to forge diplomatic relations with Beijing in 1975.