HONG KONG, China -- Hong Kong announced Sunday it will halve the period for which it suspends international flights that bring in passengers infected with Covid-19, as the aviation industry increasingly voices alarm over the continued difficulty of operating in the city.

Once a global logistics and transportation hub, Hong Kong has imposed some of the world's harshest travel restrictions under its zero-Covid policy.

One of these measures is the city's "route-specific suspension mechanism", which previously banned an airline from flying a particular route for 14 days if three or more infections were found among a flight's passengers.

In the early hours of Sunday, the government announced the suspension period would be shortened from 14 days to a week, beginning April 1.

Airlines have been lobbying for its complete removal, but Hong Kong leader Carrie Lam said there was "no room for major relaxation" as preventing imported infections remained "a fundamental pillar of Hong Kong's anti-epidemic policy".

Last Monday, Hong Kong took its first step in easing travel restrictions as the city moves past the peak of its deadliest virus wave, saying it would lift a flight ban from nine countries from April.

But its pace of reopening still lags behind regional counterparts -- especially rival financial hub Singapore, which said last Thursday it will lift restrictions on all vaccinated travellers this week.

Last week, Bloomberg reported that 11 airlines and logistics giants had sent a letter calling for the removal of Covid-19 testing requirements for flight crews before take-off and on arrival.

"We seek a return to normal flight operations in Hong Kong, in which the city can once again serve as an aviation hub," they were quoted as saying.

But at Sunday's press conference, Lam said the government "will never be able to meet the aspirations and needs of the aviation industry".

"We are in a public health emergency, so every business has to make sacrifices... so I hope and I make an appeal that airlines will also understand."

Lam again refused to draw a detailed roadmap for the city to fully emerge from the health crisis, saying policies had to be adjusted from time to time as the situation developed.

A special committee to review her administration's handling of the epidemic "will be carefully handled by the next government as I believe", Lam said.

A 1,500-person elite committee is set to select the city's next leader on May 8 and Lam has not announced her plans to run for a new term or to retire.