A heated exchange on population numbers resurfaced tensions over immigration, leading the ruling People's Action Party (PAP) to issue a strong statement refuting opposition claims that it plans to drastically increase the number of foreigners, and questioning the character and integrity of opposition party chiefs.
During a televised debate on Wednesday night, Singapore Democratic Party (SDP) chief Chee Soon Juan suggested several times that Deputy Prime Minister Heng Swee Keat had "toyed with" the idea of nearly doubling the Republic's population to 10 million, from the current 5.7 million.
He asked Foreign Minister Vivian Balakrishnan, who was representing the PAP at the debate, if he would categorically tell Singaporeans his party had no intention of raising the population to 10 million by continuing to bring in foreigners.
Dr Balakrishnan corrected him each time and referred him to the National Population and Talent Division's statement that the Government had no plans to do so.
But Dr Chee doubled down on the claim, publishing a Facebook post linking to a Straits Times report of a dialogue DPM Heng had with Nanyang Technological University students in March last year.
ST clarified that Mr Heng did not say Singapore should plan for 10 million people, nor did he mention the figure, at the event.
On the contrary, when asked about the Population White Paper - which projected that Singapore's population could hit 6.5 to 6.9 million by 2030 - Mr Heng noted that former chief planner Liu Thai Ker had publicly said Singapore "should go for an even higher number".
Without endorsing this, he had explained that "our population size was not just about physical space, but also about social space and how we can preserve a sense of togetherness".
It was the former Housing Board chief executive, Mr Liu, who had suggested Singapore should actually plan for a more distant future if it was to remain a viable, liveable city.
At a public forum in April 2013 on the topic of planning for 2030, Mr Liu said: "The world doesn't end in 2030, and population growth doesn't end at 6.9 million."
ST reported him suggesting that Singapore could do well to look ahead, perhaps to 2100, when it might have a population of 10 million.
Mr Heng refuted Dr Chee's statement on Thursday in a Facebook post: "Let me be clear: The Government has never proposed or targeted for Singapore to increase the population to 10 million. And if we look at today's situation, our population is likely to be significantly below 6.9 million by 2030."
Later that day, Dr Balakrishnan also called on Dr Chee to clarify his stance, now that the 10 million figure touted in the party's manifesto had turned out to be a falsehood.
The SDP, however, said in a press release: "Now that Dr Chee has successfully extracted an assurance from the PAP that it has no intention of increasing the population to 6.9 or 10 million, we invite the PAP to tell Singaporeans what its target population is."
When the controversial Population White Paper was published in 2013, it drew negative reactions from many quarters, in particular, over its projection that Singapore's population could reach 6.9 million by 2030.
In a nod to its campaign slogan 4Y 1N - which hinges on getting people to say "no" to a 10 million population - the SDP added: "The idea of a 10 million population is not an SDP invention or imagination."
This prompted the PAP to say that having been proven wrong, the honourable thing to do would have been to "admit that SDP's election campaign was based on a falsehood, withdraw it, and apologise to Singaporeans for misleading them".
"Instead, Dr Chee further twists the facts... Dr Chee first conjures a bogey out of thin air to befuddle, frighten and divide Singaporeans," said the PAP. It added that when it was pointed out no bogey existed and no one had "toyed" with the idea, "he waves his arms triumphantly in the air, proclaiming, 'see, I slayed the bogey'".
Pointing out that Dr Chee has "staged this drama many times before", the PAP statement said that the "new Dr Chee - of which there have been many - is still the old Dr Chee".
The party went on to say that this is not just a matter of Dr Chee's personal dishonesty, but that the falsehood renders the campaign "pointless" and calls into question the integrity of the whole party.
Weighing in on Friday, Workers' Party (WP) chief Pritam Singh said there should be room for fair comment on the population target that Singapore is aiming for, since ministers have alluded in the past to the possibility of a larger population size.
While he acknowledged that Dr Balakrishnan had said that Singapore was not even going to reach a population of 6.9 million, he said: "So one of the things I don't understand is why can't these things actually come up well before the elections. I mean it's the Government's position so it should state that very clearly."
In response, the PAP issued another statement on Friday expressing disappointment that Dr Chee and the SDP had "dug their heels in, repeated their falsehoods, and refused to apologise to Singaporeans for misleading them", and that other opposition leaders had "also opportunistically jumped into the fray".
"It is baffling that Mr Singh should ask this question (on why the Government could not have said this earlier). During the Committee of Supply in February 2018, Minister Josephine Teo had said that our population would be significantly below 6.9 million in 2030," it said.
"She repeated this in the Committee of Supply in February this year. Was the leader of the opposition not scrutinising the minister's statements?"
Taking this up yesterday, Law and Home Affairs Minister K. Shanmugam said he was "perplexed" by the WP leader's statements, as the figures had been disclosed in Parliament more than once.