Representatives from Beijing interrupted the opening to the Kimberley Process meeting in Perth to pressure the hosts into ejecting a group of observers from Taiwan, the Sydney Morning Herald reports.

The delegation reportedly used their microphone to speak over a senior Australian official, who was introducing Foreign Minister Julie Bishop. The Chinese delegates continued to cause a disturbance until a point of order addressing the presence of Taiwanese participants was introduced as the first item on the meeting’s agenda.

A high-level Australian attendee told the Sydney Morning Herald that “It was extraordinary, so uncalled for and so inappropriate, and so disrespectful.” An Australian diamond executive also described the scene as a “shocking act of disrespect.”

Australia’s Department of Foreign Affairs and Trade said it raised concerns over the Chinese delegation’s behavior with the country’s ambassador. However, Canberra acceded to the delegation’s demands and asked the Taiwanese observers to leave the conference.

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China considers Taiwan, a democracy of more than 23 million people and the ninth-biggest economy in Asia, a breakaway province that will one day be reunited with the mainland, and regularly blocks its participation in international events. Tensions between Beijing and Taipei are fraught, particularly after U.S. President Donald Trump received a phone call from Taiwan President Tsai-Ing Wen and threatened to renegotiate the “one China” principle, which states both Taiwan and the mainland are part of the same nation.

First initiated in 2000, the Kimberley Process is a meeting that brings together governments, industry and civil society to stop the trade of rough diamonds used by rebel movements to finance wars against legitimate governments.

[SMH]