Singapore’s Civil Aviation Authority (CAAS) has temporarily suspended the Boeing 737 Max fleet of aircraft from flying into and out of the country.
The decision comes after an Ethiopian Airlines Boeing Max 8 crashed on Sunday, killing 157 people on board.
It was the second fatal accident involving that model in less than five months.
Singapore’s Changi Airport is the world’s sixth busiest and a major hub connecting Asia to Europe and the US.
But only a handful of airlines operate Max aircraft in and out of the country.
Several airlines and regulators around the world have already grounded the Max 8 model following the crash.
Singapore is believed to be the first country to ban all variants of the Max fleet of aircraft. The suspension went into effect from 14:00 local time (06:00 GMT).
Is disruption likely?
Singapore’s aviation authority said the affected airlines include SilkAir, which operates six Boeing 737 Max 8 aircraft, as well as China Southern Airlines, Garuda Indonesia, Shandong Airlines and Thai Lion Air.
It said it is working with airlines and Changi Airport to minimise the impact on passengers. Experts told the BBC that disruption was likely, however.
Aviation consultant Ian Thomas of CAPA Consulting said: “This is sure to lead to significant flight cancellations and disruption to schedules as the airlines involved switch to other aircraft types (assuming they are available).”
The BBC’s Karishma Vaswani, who is at Changi Airport, reports orderly scenes. Some flights have been cancelled but it is not known if the suspension is to blame.
In the US, the country’s Federal Aviation Administration told airlines on Monday it believes Boeing’s 737 Max 8 model to be airworthy, despite the two fatal crashes.