All bars, restaurants and gyms will be ordered to shut down from midnight on Tuesday, the Prime Minister announced on Monday, amid mounting measures to combat the coronavirus.
Clubs, cinemas and other areas where the public gather will also be shut though take-away outlets will not be impacted.
But Robert Abela said the health authorities had once again confirmed there was no need for a total country lockdown for the time being.
"We don't want to go towards the total lockdown button. So far, the health authorities are not indicating that we need to press the red button. If we go there, the consequences will be massive. If we go for a total lockdown it's going to have to be considerably longer than three weeks. But it might be needed... the priority is people's health," Abela told a news conference.
If we go for a total lockdown it's going to have to be considerably longer than three weeks
Abela was speaking after the health authorities said nine cases had been confirmed since Sunday of which three were, for the first time, locally transmitted cases. The total number of COVID-19 cases in Malta is now 30.
He also announced that the fines for those breaking the newly-announced quarantine law will increase from €1,000 to €3,000.
The prime minister urged all residents in Malta who are currently overseas to return to Malta as soon as possible.
"All those residents outside Malta should return at once. The tourists should leave as soon as possible," he said.
"These are not the best of times. But the more we cooperate the sooner we will get out of this crisis," Abela said.
Avoiding a 'tsunami'
Health Minister Chris Fearne said it is important to control the flow of the virus over a period of time, rather than face a "tsunami".
He underlined the importance of "social distancing" and urged the elderly to stay indoors for the time being.
Fearne said all efforts are being done to reduce the rate of virus cases in Malta.
"We need to ensure our health system can cope," Fearne said, acknowledging the anticipated prolonged fight against the virus will hurt the economy.
Home Affairs Minister Byron Camilleri said the police's Administrative Law Enforcement Unit was working around the clock to enforce the quarantine measure.
A total of 376 inspections have been carried out and five have been fined.
Community officers will be deployed to help distribute medicines to elderly people and others in quarantine.