“The mudik ban will be effective starting Friday, but sanctions [for violators] will be enforced starting May 7,” Coordinating Maritime Affairs and Investment Minister Luhut Pandjaitan said in a video conference on Tuesday.

Luhut said that, under the mudik ban, travel in and out of virus-hit areas, also known as COVID-19 red zones, would be prohibited. The ban applies to Greater Jakarta, the nation’s epicenter of the coronavirus outbreak.

Despite the ban, Luhut, who is also the acting transportation minister, said public transportation across Greater Jakarta would continue to operate to make it easier for those who still needed to commute to work, such as health workers and hospital service staff.

“The relevant ministries and institutions will take immediate steps to prepare for operational technicalities in the field, including ensuring the flow of supplies. As such, toll roads will not be closed,” he said.

Read also: COVID-19: 'Mudik' risks mass contagion across Java

President Joko “Jokowi” Widodo earlier announced his decision to ban mudik after reviewing a Transportation Ministry survey that showed that 24 percent of respondents had plans to travel home.

The same survey indicated that around 7 percent of respondents had already left on mudik trips.

The decision to implement the ban comes days ahead of Ramadan, which is predicted to start on Friday.

Regional heads across Java have reported that many local residents of areas in Greater Jakarta had returned to their hometowns. It is suspected that some cases of COVID-19 could be linked to these travelers.

The Transportation Ministry’s Land Transportation Directorate General and the Jakarta Transportation Agency have each canceled their annual free Idul Fitri mudik programs this year, which normally involve hundreds of thousands of participants.

Before the decision, Jokowi had only advised the public not to participate in the exodus and ordered regional heads to find ways to discourage people from traveling, while prohibiting only government workers from going on mudik trips.

He also previously made efforts to discourage homebound travel by expanding social aid programs, as many travelers were forced to go home after losing their jobs or seeing business slow down.

Luhut explained that the government decided to completely ban mudik only after it started distributing social aid because it was important that a social safety net was first put in place.

“The government’s strategy was like what we know in the military – a gradual, graded and continuous strategy. So we were not rushing because everything must be prepared carefully and thoroughly,” Luhut said.

Read also: ‘It’s too late’: Lawmakers criticize timing of Jokowi’s ‘mudik’ ban

Annually, some 20 million people from Greater Jakarta travel to their hometowns to celebrate Idul Fitri with their families.

Religious Affairs Minister Fachrul Razi said his ministry had been coordinating with Islamic leaders and organizations, including the Indonesian Ulema Council (MUI), to send the word out on the ban.

“The most important thing for us is that we are still carrying out compulsory fasting as best as possible. We just don’t have to go home on a mudik trip as that would bring more harm than good right now,” Fachrul said.