After serving as a test run globally for how to return to the office safely, banks in Hong Kong reinstated work-from-home arrangements for many of their staff this week as a “third wave” of coronavirus cases hit the city.

HSBC, the biggest of three banks authorised to issue currency in the city, “strongly encouraged” its staff to work remotely beginning on Wednesday until further notice, particularly those with pre-existing medical conditions.

“To support flexible working, employees who must work from HSBC premises should discuss working arrangements, including staggered arrival and lunch times, with their line manager,” HSBC said in a memo late on Tuesday.

A HSBC spokeswoman confirmed the contents of the memo on Wednesday.

Banks in Hong Kong were some of the first globally to return to the office en masse beginning in May as the coronavirus pandemic forced financial centres from New York to London to Singapore to close offices as part of the world’s biggest work-from-home experiment.

The coronavirus, which causes the disease Covid-19, has infected more than 13.3 million people worldwide.

The International Commerce Centre (ICC) in West Kowloon and other office towers in the city reprogrammed lifts to carry fewer passengers. Banks installed privacy screens on trading desks and at bank teller locations to prevent the spread of droplets between colleagues and customers. Conferences in the city, as well as business meetings, went virtual.

But, the city ordered some of its strictest social-distancing measures so far this week after a surge in new locally transmitted cases, including a requirement that passengers wear masks on public transit. Bars, karaoke rooms and gyms were among a dozen businesses ordered closed beginning Wednesday and restaurants can only provide takeaway after 6pm.

BNP Paribas said in an internal memo this week it would begin splitting teams and suspended travel by employees between different floors in its buildings and visits by staff between its offices in the city. The bank asked employees to limit any meetings to no more than eight people, per city guidelines, and to “consider the necessity of planning further in-person meetings – both internal and external”.

A BNP Paribas spokeswoman declined to comment on Wednesday.

As a result of the surge in cases, Citigroup is pausing its plans to bring more people back to the office in Hong Kong, with 70 per cent of its staff in the city now working from home. About 50 per cent of its staff worked from home before the pause.

Deutsche Bank asked “non-critical staff” to work from home when possible, whilst Nomura encouraged the bulk of its staff to return to working from home as much as possible. Nomura had returned fully to the office last week.

Standard Chartered encouraged its employees to work from home where possible and put a “hard-split team” arrangement into effect for employees who had to work in the office to reduce the risk of infection, a spokeswoman said.

Branch staff will work from home one day each week to reduce physical contact and branches will close temporarily for deep cleaning and disinfection if there is a confirmed case nearby, she said. Customers are required to wear masks and undergo temperature checks when visiting its branches in the city.