Hong Kong has barred until mid-April incoming passenger flights from Singapore operated by Singapore Airlines, after an arriving passenger tested positive for Covid-19 infection.
Three passengers on the carrier's March 31 flight also failed to comply with disease precautions, Hong Kong authorities said on Friday.
Singapore Airlines confirmed the order but said passenger services from Hong Kong to Singapore would not be affected by the suspension, which runs until April 16.
A transit passenger on the SQ882 flight had a negative pre-departure test result, but subsequently tested positive on arrival in Hong Kong, the airline said.
"SIA has taken immediate steps to strengthen checks at the point of embarkation to ensure our customers are in compliance with Hong Kong's regulatory requirements," it said in a statement.
It would help health authorities in their efforts to trace those who had contact with the infected person, it added.
The other three non-compliant passengers were also transit passengers who went through pre-departure tests at clinics in their places of origin that fell short of Hong Kong's requirements, Singapore's aviation regulator said.
All three passengers were tested negative, the Civil Aviation Authority of Singapore (CAAS) said.
Hong Kong has set trigger points that warn airlines of suspension under its Covid-19 test requirements for arriving air passengers, one of which Singapore Airlines had breached, CAAS added.
Singapore has reported relatively few coronavirus cases in recent months, adopting tight entry curbs and rules to rein in domestic transmission.