The National Solidarity Party (NSP) will not contest in Marine Parade and MacPherson at the next general election, to avoid clashing with the Workers' Party (WP).
In a statement yesterday, NSP said it was taking the "difficult decision" in recognition of "voters' desire for greater opposition representation in Parliament".
Meanwhile, the Singaporeans First party will not be contesting in Ang Mo Kio GRC, said the party's secretary-general, Tan Jee Say, in a statement yesterday.
"To avoid a three-cornered fight, SingFirst will hereby withdraw its interest to contest Ang Mo Kio GRC and focus its resources on Tanjong Pagar and Jurong GRCs," he said.
The move paves the way for the Reform Party, led by Kenneth Jeyaretnam, to contest in a straight fight with the People's Action Party (PAP) team in the GRC, which is helmed by Prime Minister Lee Hsien Loong.
Yesterday's announcements mean that all potential three-cornered fights involving opposition parties have been avoided.
NSP acting secretary-general Hazel Poa said: "Multi-cornered contests are likely to dilute opposition votes and reduce the chances of a more diverse Parliament. We trust that the WP will send in good candidates and give voters in these two constituencies a choice."
In a Facebook update yesterday, WP chairman Sylvia Lim thanked NSP for announcing its decision early.
Ms Lim said: "WP will continue to focus on its preparations and campaign on the 10 constituencies announced."
Both parties had stood firm about contesting in Marine Parade GRC and MacPherson SMC during meetings on three-cornered fights last week among opposition parties.
WP made an offer to give up MacPherson, in exchange for NSP staying away from Marine Parade, but it was rejected by NSP, said Ms Lim during a walkabout on Friday.
Yesterday, Ms Poa revealed that her party had informed WP in an e-mail on Friday of its decision to pull out of both constituencies, and was hoping to issue a joint statement about it "as a symbol of co-operation".
However, she said, WP did not respond.
Opposition parties met twice last week, on Monday and Thursday, to discuss who should contest in which constituencies against PAP. WP attended only the first meeting, saying that it had already made its intentions clear.
Ms Poa said that "had the WP been present at Thursday's meeting, the issue could have been resolved".
She added: "As there are many who are anxious for an outcome, NSP decided not to delay any further, but to make this announcement on our own."
NSP had contested in Marine Parade GRC in the last election, polling 43.4 per cent of valid votes against the PAP's 56.6 per cent.
After giving up both constituencies, NSP will now contest in Tampines and Sembawang GRCs and Pioneer SMC at the next general election.
Ms Poa thanked the Singapore Democratic Party for "voluntarily withdrawing from Sembawang GRC in the interest of opposition unity".
Additional reporting by Charissa Yong
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