The adjustment was made in less than 12 hours since the isolation rule came into effect, after several officials and business representatives expressed concerns that the quarantine rule might disrupt work of around 16,000 people who travel to work between HCMC and Dong Nai every day.

On Friday, Dong Nai announced that starting Saturday, all arrivals from HCMC must quarantine themselves at home or accommodation facilities for 21 days.

In addition to quarantine, those people must visit healthcare facilities in Dong Nai to get new coronavirus tests on the seventh and 14th days starting from the day they set foot in the province, bearing all related costs themselves. Anyone failing to follow these regulations would be dealt with in accordance with the law.

Addressing a meeting on Covid-19 prevention Friday, Bui Ta Hoang Vu, director of the HCMC Department of Industry and Trade, said: "Dong Nai is very important in terms of trade with HCMC and this regulation could affect consumption."

Dong Nai had issued the isolation rule as the province worries HCMC's ongoing Covid-19 cluster could spread further.

The cluster emerged on May 26 from a Christian congregation called Revival Ekklesia Mission based in HCMC’s Go Vap District. Infections were first detected among its members before the virus spread to 21 of the city's 22 districts, and then to other provinces in the south and Central Highlands.

HCMC is now the fourth worst hit locality, with 324 cases, compared to more than 5,200 nationwide as part of the ongoing Covid-19 wave that hit Vietnam more than five weeks ago.

According to HCMC Export Processing Zone and Industrial Park Authority (HEPZA), Dong Nai’s isolation measure directly affects labor movement between HCMC and Dong Nai, the transportation of production materials, as well as the circulation of goods between.

Companies in export processing zones (EPZs) and industrial parks (IPs) across HCMC will not be able to maintain production.

Data from HEPZA shows more than 6,000 laborers from Dong Nai come to work at five EPZs and IPs of Cat Lai, Linh Trung, Binh Chieu, Le Minh Xuan 3 and Dong Nam in HCMC every day aside from the city’s hi-tech park, while goods are transferred to and from the two provinces on a frequent basis.

Meanwhile, Dong Nai authorities said every day, as many as 10,000 laborers and experts, including foreigners, come to work at local industrial zones from HCMC.

Le Bich Loan, deputy head of the management board at Saigon Hi-Tech Park in Thu Duc City, said many companies were worried about the isolation rule, prompting the park to ask the city administration for help Friday.

Ho Xuan Lam, deputy head of the HCMC Federation of Labor, said if laborers and businesses were to be affected directly by the rule then it is not possible to meet the dual goals Vietnam has been pursuing, which are fighting the pandemic and maintaining socio-economic development.

Commenting on the quarantine rule, Thai Bao, vice chairman of Dong Nai, told VnExpress on Friday the number of laborers moving daily between the two localities is way too big, posing a very high risk of Covid-19 infection.

His HCMC counterpart Duong Anh Duc said the two localities should "work this out to find the most reasonable solution to avoid too many impacts on business production and goods transportation."

According to the adjusted rule, experts, factory workers, and other employees from HCMC are still allowed to ride shuttle buses operated by their companies to enter Dong Nai, yet the companies must register these buses along with the pick-up and drop-off addresses with authorities.

The number of passengers on these buses must be less than half of their full capacity, and all passengers on board must strictly follow Covid-19 protocols, including wearing masks and keeping a distance from one another.

Those traveling into the province in personal vehicles must comply with body temperature measurements and medical declarations at quarantine checkpoints.

A number of localities across Vietnam, including Long An, which borders HCMC to the south, have requested isolating everyone coming from the city.

Some like Da Nang and Hue even demanded HCMC arrivals stay in centralized quarantine camps.