Former Singapore People's Party member Benjamin Pwee has pulled out of the Punggol East contest as the snap election meant he did not have enough time to conclude talks with opposition parties to run under their banners.
Mr Pwee told The Sunday Times that he was in "deep negotiations" to take over the helm of "a major longstanding party" and contest the by-election, but "there was just not enough time" to hold a party congress to bring him into the party before Nomination Day, which is on Wednesday.
He also said that if a large number of opposition candidates are fielded, which now looks likely, it "could end up eroding not just the PAP's vote, but also the WP's vote".
Mr Pwee did not name the party he was in talks with but earlier, Mr Seow Khee Leng, secretary-general of the Democratic Progressive Party, said he would be handing over his mantle to Mr Pwee.
A former government scholarship holder, Mr Pwee, 44, contested in the 2011 General Election as a candidate for Mr Chiam See Tong's Singapore People's Party in Bishan- Toa Payoh GRC.
In January last year, he quit the party with five other members over differences in the party's leadership style and direction.
On Saturday, he said his sights are still trained on the 2016 General Election.
He will be meeting his supporters to explain his decision tonight.
"I wish all candidates the very best, and call for a clean and gentlemanly fight," he added.
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