“Abrupt” move to break diplomatic relations condemned by Taipei as main rival China gleefully welcomes the decision.

Taiwan has condemned the tiny African nation of Sao Tome and Principe’s sudden move to break formal diplomatic ties with the self-ruled island, a decision that was warmly welcomed by rival China.

Taiwan “regrets the Sao Tome and Principe government’s abrupt and unfriendly decision, and condemns this action”, a statement said on Wednesday.

China’s foreign ministry said it welcomed “Sao Tome back onto the correct path of the ‘one China’ principle”, according to which Beijing considers Taiwan part of its territory.

However, the ministry did not say explicitly that China had now established relations with the former Portuguese colony.

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Just 21 countries and governments now have official ties with Taiwan. Most of the world and the United Nations do not formally recognise the island as a condition of maintaining relations with China.

Taiwan’s presidential office said China’s use of Sao Tome’s financial woes to push the “one China” principle will damage stability across the Taiwan Strait.

Beijing and Taipei have competed for allies for most of nearly seven decades since the end of China’s civil war in 1949, when the defeated nationalist government fled across the Taiwan Strait and based itself on the island.

Tense relations

Relations between China and Taiwan have been tense since the December 2 telephone conversation between US president-elect Donald Trump and Taiwan President Tsai Ing-wen.

It was the first such contact with Taiwan by a US president-elect or president since Jimmy Carter adopted the “one China” policy in 1979 and broke off formal diplomatic relations with the island.

The Trump-Tsai call infuriated China, which accused Taipei of playing a “trick” and later warned Trump about challenging Beijing on the issue of Taiwan.

China’s foreign ministry did not mention the call in its Wednesday statement, saying only that its “one-China policy” was the “political foundation for China to maintain and develop friendly and cooperative relations”.

Sao Tome and Principe is an island nation off the coast of central Africa, with a population of almost 200,000. The impoverished former Portuguese colony relies heavily on foreign aid.

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Taiwanese Foreign Minister David Lee accused Sao Tome of demanding “an astronomical amount of financial help”, though he did not say how much. A Taiwanese foreign ministry statement accused Sao Tome of trying to “gain a higher price by lingering on both sides of the strait”.

As its economic, military and political clout has grown, China has become more successful in pulling away governments in an effort to diplomatically isolate Taiwan, though countries such as the US maintain strong unofficial ties with Taipei.

Washington is Taiwan’s most important political ally and sole arms supplier, despite the lack of formal diplomatic ties.