Qatar Airways has extended its cabin crews' nightly curfew after some stewards allegedly broke the Gulf country's strict virus control rules, according to a memo seen by AFP Thursday.

Qatar has imposed some of the world's strictest measures to combat coronavirus including a limit of five people at social gatherings and mandatory masks in public places. "It has been disheartening to learn that there have been several instances of failure to adhere to the government regulations... among our cabin crew team," the airline's senior vice president of cabin services wrote to crew on August 11.

"We respectfully request that crew members refrain from participating in any gatherings or social events of any kind. Crew curfew hours will also be extended to commence from 9 p.m. until 7a.m. with immediate effect until further notice whilst COVID-19 precautionary measures are in place."

They had previously been required to return to their company-provided accommodation between 4 a.m. and 7 a.m.

Before coronavirus, Qatar Airways cabin crews were a mainstay of Doha's small circuit of bars and clubs, drawn by special discounts for airline employees. While bars and clubs remain closed in Qatar, restaurants that serve alcohol have begun to re-open with several creating areas specifically for drinkers.

Qatar has reported 114,281 COVID-19 cases since the start of the pandemic -- more than 4 percent of its 2.75 million people -- but most have recovered and only 190 people have died. The Gulf airline, which flew to more than 170 destinations with 234 aircraft as of March, has been hit by airport closures and travel bans imposed to contain the spread of the COVID-19 disease.

It has previously warned cabin crew and pilots that they face sweeping redundancies and pay cuts as the airline battles the global aviation downturn.

The International Air Transport Association warned in April that air traffic in the Middle East and North Africa would plummet by more than half this year.

"For the ongoing protection of our cabin crew, colleagues, fellow residents and passengers, this temporary restriction is designed to limit any potential new cases of COVID-19," the airline said in a statement. 

"We appreciate the incredible continued efforts of our crew to go above and beyond during this challenging time and this temporary measure will further protect all individuals."