Former Taiwan premier Frank Hsieh on Monday announced plans to visit China, a trip which would make him the most senior politician from the China-sceptic opposition party to visit the mainland.
The visit, described by local media as "ice-breaking", came amid debate in the party about whether to change its China policy.
Hsieh, who was premier from 2005 to 2006 and retains major influence in the Democratic Progressive Party (DPP), told reporters he would leave Thursday.
"The purpose of the trip is to build mutual trust," said Hsieh, declining to say if he would meet Chinese government officials during the five-day visit.
Hsieh's first stop will be the southeastern coastal city of Xiamen, followed by a visit to nearby Dongshan Island where his ancestors lived before emigrating to Taiwan.
Later, the trip will take him to Beijing, where he plans to visit the Olympic stadium and attend an international cocktail contest as a guest of the International Bartenders Association.
Voters in January re-elected President Ma Ying-jeou of the Kuomintang party, endorsing the Beijing-friendly policies he has pursued since he took office in 2008.
Since then, leading DPP members have debated whether their party needs to change its China policy, in part to reflect Beijing's fast-expanding regional and global influence.
"The DPP should face the reality of China's rise...if the DPP keeps refusing to change its position and let the Kuomintang and the Chinese communist parties work hand in hand, I'm afraid the DPP will never be able to get back into power," Hsieh said.
Hsu Yung-ming, a political science professor at Taipei's Soochow University, told AFP that "although the party authorities have not decided to amend their China policy at the moment, the results of the visit could be used as a key reference in the future".
Tensions between Taipei and Beijing soared in the eight years to 2008 when then-president Chen Shui-bian of the DPP repeatedly ruffled Beijing's feathers.
China and Taiwan have been ruled separately since the end of a civil war in 1949. But Beijing still claims sovereignty over the island and has threatened to invade should it declare formal independence.