Vera Liu, a Singapore property agent, was panicking in the wee hours of Thursday morning after new property taxes saw two of her deals fall through.

Singapore raised levies on private property purchases in a surprise move late on Wednesday night to cool the market, including a doubling of stamp duties for foreigners to an eye-watering 60%.

Liu’s foreign buyer pulled out of a purchase of a S$10 million ($7.50 million) luxury condominium along Singapore’s Orchard Road shopping belt, while another interested buyer who already transferred funds into Singapore is also holding off.

“The door is now closed (to foreign buyers),” said Liu. “I was panic calling my buyers near midnight, it’s crazy, the adjustment is so high. It could mean a few million dollars more in duties for some buyers.”

Ever since a run on purchases in 2018, the government has timed announcements of any tightening moves closer to midnight. The new rates came into effect on Thursday.

The hike in duties is one of the harshest tightening moves in the market in a long time and comes after a rush of foreigners back into Singapore’s property market in recent years.

Policymakers are growing concerned that foreign investors increasingly see Singapore property as a hot asset class, squeezing out locals.

National development minister Desmond Lee said without “early pre-emptive measures, we may see investment numbers, both by locals and by foreigners grow, and that will add stress to Singaporeans who are looking to buy residential property”.

While taxes were also increased for local buyers of second and subsequent properties, analysts expect the largest impact to be felt by foreign buyers of luxury properties.

The government said the new rates would impact about 10% of private property transactions.

Christine Sun, the senior vice president of research & analytics at OrangeTee & Tie, called it a “freezing measure” for foreign buyers.

“Luxury home sales may experience more impact and a temporary pullback in demand from these buyers.”