Already chilly cross-strait ties have worsened with the coronavirus outbreak as mistrust between Beijing and Taipei has led to acrimony in the handling of the crisis.

With the two sides unable to agree on evacuation procedures, several hundred Taiwanese are still stranded in the epicentre of the disease outbreak, the central Chinese city of Wuhan.

A war of words between the two sides was accompanied by the roar of fighter jets over the Taiwan Strait recently .

Ties between mainland China and self-ruled Taiwan, which Beijing regards as a breakaway province to be reunified by force if necessary, have been chilly since President Tsai Ing-wen of the independence-leaning Democratic Progressive Party came to power in 2016. Over the last four years, China cut off official communications that were established during the rule of Ms Tsai's predecessor, the China-friendly Ma Ying-jeou, and squeezed Taiwan's economy and international space among other moves.

The relationship worsened during and after the presidential and legislative polls last month that Taipei has accused Beijing of trying to influence, particularly as Ms Tsai won re-election resoundingly and her party retained its majority in Parliament.

China at first refused to entertain Taiwan's request to evacuate Taiwanese living in Wuhan but in an about-turn allowed 247 to be evacuated on Feb 4, not on a Taiwanese airplane but a Chinese airliner. To Taipei's chagrin, some on its original name list were not on the plane, while some not on the list were on it, including Chinese spouses of the Taiwanese, whereas it had wanted only Taiwanese sent back.

The two sides then argued over how and when the next batches of Taiwanese should be evacuated. China wanted to send some 970 people back on several planeloads between Feb 6 and 8, while Taiwan, which had earlier asked for the repatriation of 500 people, said it could not cope with quarantining such a large number of people at short notice. It asked instead for the elderly, minors and those with chronic diseases to be evacuated first.

The two sides have yet to agree on how the evacuation is to be done.

China's Taiwan Affairs Office (TAO) has accused the DPP government of throwing out "cold-blooded measures which are full of discrimination to impede Taiwan compatriots stranded from returning to the island" adding it has "sacrificed the lives and health of Taiwan compatriots for their political interests".

Their quarrel spilled over into the international arena when Taiwan asked to be included in meetings of the World Health Organisation (WHO) on the coronavirus crisis on the basis that it had several cases of Covid-19 and needed full and timely information to deal with its own outbreak.

Taiwan is not a member of the World Health Organisation (WHO), which as a United Nations body is open only to nation-states, but was an observer to its decision-making World Health Assembly from 2008 to 2016, after which it was blocked by China from attending the annual meeting.

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Showing its mistrust, China slammed Taiwan's bid to take part in WHO meetings as an attempt by Taiwanese separatist forces to broaden the island's international space.

"We will continue to make arrangements for Taiwan to obtain relevant information on epidemic prevention and control as part of China, but we will never allow any act to seek 'Taiwan independence,'" an official of the TAO told the media.

In the end, as international pressure mounted, with the US and Japan weighing in, Beijing relented and Taiwan's experts were able to take part online in a WHO conference this month (February) in their personal capacities.

It was not without a war of words though, with Beijing insisting the Taiwanese took part with its consent and Taipei saying it did so after negotiating directly with the WHO and accusing China of politicising a public health issue.

What further heightened tensions between the two sides were Chinese fighter jets circling the island not once but twice on Feb 9 and 10. One of the flights breached briefly a median line in the Taiwan Strait between the two sides, violating a tacit agreement between the two sides not to do so.

Taiwan scrambled its own aircraft in response and President Tsai put out a statement calling the move at a time of "the outbreak of Wuhan pneumonia" not only meaningless but also unnecessary. She added that Beijing should "quickly control" the outbreak to "ease regional and global tensions".

China, for its part, called the flights exercises of the People's Liberation Army (PLA) to "safeguard national sovereignty and territorial integrity" and accused the DPP of continuing to make separatist comments and new moves to seek independence.

Analysts have said the move was to divert attention from the internal coronavirus crisis and demonstrate that the PLA's combat-readiness is not affected by the outbreak. But it has brought in the Americans.

In an apparent show of support for Taiwan and to warn China against pressuring the island, the US on Feb 12 flew two surveillance aircraft over the Taiwan Strait and two B-52 bombers close to the island and on Feb 15 sent a warship through the Strait.

It did not help matters that Taiwan's Speaker of Parliament Yu Shyi-kun at a meeting with the de facto American envoy in Taipei on Feb 13 urged the US to formally recognise Taiwan.

The Chinese responded quickly by accusing Mr Yu of spreading a "political virus".

"Instead of thinking about how to safeguard the lives and common interests of people, he took advantage of the novel coronavirus outbreak, hurt the feelings of the Chinese people, and harmed the cross-Strait relations," said Mr Ma Xiaoguang, spokesman for the TAO.

The coronavirus outbreak could have been an opportunity for the two sides to mend ties by cooperating to fight a common "enemy".

Instead, it has contributed to a bad start to the second term of President Tsai, making the next four years of cross-strait ties even more fraught and uncertain.