What could have triggered the new cooling measures?

Experts say it has something to do with million-dollar flats.

Property experts said the steep price growth at the upper tier of the HDB resale market may have pushed the government to implement new cooling measures.

According to OrangeTee's Senior Vice President of Research and  Analytics, Christine Sun, prices of larger HDB flats like 5 room and executive rose 2% MoM and 1.9% MoM, respectively, in September.

To add, 45 million-dollar flats were sold in September, the highest for the single month.

"The data indicates that price growth has indeed been much faster at the upper tier of the HDB resale market," she said.

Mohan Sandrasegeran, a senior analyst at One Global Group, also believes that the accelerating price increase in both mature and non-mature estates and the " seemingly relentless strength in the rise in million dollar deals" likely elicited the latest round of cooling measures.

 Sandrasegeran, however, said the momentum of million-dollar deals will likely show signs of slowing down in the upcoming quarters as a result of the recent property cooling measures.

Sun said the slowdown will be seen particularly in the price growth of bigger flats due to the wai-out period, but smaller flats will likely not be affected.

"Prices of some smaller flats may continue to rise and we may see a higher proportion of million-dollar flat transactions coming from 4-room flats in future," she said.