TAIPEI • Mr Terry Gou, the billionaire founder of iPhone assembler Foxconn Technology Group, yesterday threatened to throw Taiwan's presidential race into turmoil as he took a key step towards running as an independent.

Mr Gou withdrew from the opposition Kuomintang (KMT), a necessary precursor to mounting a third-party challenge against Taiwanese President Tsai Ing-wen.

The move came despite a last-minute plea from senior KMT leaders, including Ms Tsai's predecessor Ma Ying-jeou, for Mr Gou to back their nominee and help return the China-friendly party to power.

Mr Gou has until next Tuesday to apply to run in the Jan 11 election.

"I know I'm doing the right thing, something major that will turn around Taiwan's destiny," Mr Gou said in a statement.

Mr Gou's candidacy would shake up Taiwan's political landscape, undercut KMT challenger Han Kuo-yu's effort to unseat Ms Tsai and potentially weaken both dominant parties. A three-way race could be a hard-fought affair, with Ms Tsai leading with 33.7 per cent of support, compared with 28.9 per cent for Mr Han and 25.6 per cent for Mr Gou, according to a survey released on Tuesday by the Apple Daily newspaper.

Since both Mr Gou and Mr Han support closer ties with China, the Foxconn founder could complicate KMT's bid to oust Ms Tsai and her pro-independence Democratic Progressive Party.

Mr Gou has continued to publicly flirt with the idea of a presidential bid despite losing the KMT primary to Mr Han in July. Mr Han said he regretted Mr Gou's move to withdraw from the KMT.

Mr Gou has been sending signals that he might mount an independent run for weeks, although he will still need to collect around 280,000 signatures to get on the ballot.

After assembling a campaign team, he confirmed last month that he was considering breaking from the KMT for a standalone bid.

"This conservative, hidebound party leadership is putting their own interests ahead of their party's, and the party's interests ahead of the nation's," Mr Gou's spokesman, Ms Evelyn Tsai, told reporters yesterday. "Mr Gou won't miss this party."

Correction note: An earlier version of this article misspelt Mr Terry Gou's name in the headline. We are sorry for the error.