SINGAPORE - The Singapore Democratic Party (SDP) must clarify its position now that a key plank of its manifesto has been shown to be a falsehood, Foreign Minister Vivian Balakrishnan said on Thursday (July 2).

He was speaking to the media at a coffee shop in Bukit Panjang a day after a televised debate that saw him cross swords with SDP chief Chee Soon Juan over the latter's claim that Deputy Prime Minister Heng Swee Keat had mooted having a population of 10 million in Singapore. Both Dr Balakrishnan and Mr Heng have refuted this claim.

The "One No" in SDP's "Four Yes, One No" campaign message refers to a rejection of what it claims is the People's Action Party's (PAP) plan to increase Singapore's population to 10 million.

Asked whether the Government will take action against the SDP if it continues to make this claim, Dr Balakrishnan said he was unable to comment, as ministers cannot issue directions under the Protection from Online Falsehoods and Manipulation Act (Pofma) during the election period.

On why a younger 4G minister did not represent the PAP in the first televised debate on Wednesday, the 59-year-old said: "I am a 4G minister; I'm the same age as Mr Heng." Such labels do not matter, as the PAP works as a team, he added.

He said he had nothing to add on the performance of his other opponents in last night's debate - the Workers' Party's Associate Professor Jamus Lim and Progress Singapore Party's Mr Francis Yuen.

But Dr Balakrishnan, a candidate for Holland-Bukit Timah GRC, took aim at the SDP, which is contesting the "home ground" of the incumbent PAP team. Mr Liang Eng Hwa, who faces SDP's chairman Paul Tambyah in the neighbouring Bukit Panjang SMC, is a familiar face to residents there, he said.

"For the opposition, they have never really been a part of this town, never made any contributions, never showed any interest in between elections."

Mr Liang will be nominated as chairman of the Holland-Bukit Panjang Town Council if both he and the PAP team for Holland-Bukit Timah GRC are elected, he said.

Dr Balakrishnan said that while the PAP takes all challenges seriously, "we are waiting to see even at a local level what plans they have, and what serious discussions they've had with our residents".