A Boeing 747 with an undisclosed freight shipment was set to take off on Wednesday in the first direct chartered cargo flight between Taiwan and rival China.
The plane from Taiwan's leading carrier China Airlines was to be given a grand send-off before departing Chiang Kai-shek airport at 7.10 pm GMT for the more than three-hour flight to Shanghai.
"This will be a historic moment," said airline spokesman Johnson Sun, who refused to provide details of what the plane would be carrying.
According to local media reports, the 747 would be loaded with several tonnes of equipment for a Shanghai plant belonging to the Taiwan Semiconductor Manufacturing Company, the world's biggest contract microchip maker.
Direct transportation links have been cut since China and Taiwan's split in 1949 at the end of a civil war. The first non-stop direct flights over the Taiwan Strait were carried out early this year to celebrate the Lunar New Year.
Under Taipei's ban on direct links across the Taiwan Strait, all merchandise and passengers transit via third ports, normally Hong Kong.
In a relaxation of the law in 2001, Taiwan allowed limited direct trade, post and transport links known as the 'three mini links' between the islands of Kinmen and Matsu and selected ports in China's southeastern Fujian province.
Despite political tensions, China has become Taiwan's leading foreign investment destination, with an estimated 80 billion US dollars in mainland projects so far funded by the island's business community.
China is Taiwan's largest market, but the Taiwanese government is reluctant to lift the decades-old ban.
Taiwan's independence-leaning ruling Democratic Progressive Party shot down an opposition attempt in May—the third in less than a month—to vote on a bill proposing direct air links.
The main opposition parties, the Kuomintang (KMT) and People First Party (PFP), favour improved ties with Beijing and have been pushing for direct links.
China considers Taiwan part of its territory even though the island has been ruled as a de facto independent state since 1949. It threatens to invade if Taipei declares formal independence.