Singapore authorities remain “highly vigilant” over rising home prices, the central bank chief said, signaling that the red-hot market may be getting less affordable if left unchecked.

“A prolonged divergence between prices and incomes is unsustainable from a market stability perspective and undesirable from a housing affordability perspective,” Ravi Menon, managing director of the Monetary Authority of Singapore, said Wednesday.

Singapore’s residential property market has rebounded sharply during the pandemic, sparking speculation that the government may impose cooling measures for the first time since 2018. Menon’s comments add to concerns after officials previously said they didn’t want the market to run ahead of economic fundamentals.

Authorities “remain highly vigilant to the sustained increase in prices relative to income trends,” Menon told reporters at the release of the bank’s 2020/2021 annual report. The private property index was 5.6% above its pre-pandemic levels in the first quarter while nominal gross domestic product was about 4% below, he said.

Still, Menon added that he didn’t think the property market was overheating right now, “because if it’s overheated, we’re not doing our job well.”

Home prices in the city-state climbed 3.3% in the first quarter, the most since the second three months of 2018, just before authorities imposed the most recent round of tightening measures.