Who proposed the 10m population in Singapore?

https://sg.news.yahoo.com/vivian-balakrishnan-slams-chee-soon-juan-over-false-statement-of-10-million-population-plan-171015707.html

It was Liu Thai Ker who proposed the 10m population in SG.  Why didn't the government debunk the false claim by Liu Thai Ker?

https://www.businesstimes.com.sg/top-stories/singapore-should-plan-for-population-of-10m

The population whitepaper projected a 6.9m population in Singapore by 2030.  Please look at my screenshot taken from the government whitepaper.