This follows a spike in Covid-19 cases and deaths over the past weeks, which saw the government introducing localised lockdowns in some areas around the country, the Xinhua news agency reported.
In a statement, Mnangagwa said the new measures, which are with immediate effect, will run for the next two weeks.
Among other measures, business hours for commerce and industry have been reduced and the industry has to decongest workplaces to 40 per cent while inter-city movement has been banned, except for production and distribution of food and medicines.
Commercial transport will continue to operate to allow the economy to continue to run, the president said.
Mnangagwa said travelers from countries with Alpha and Delta Covid-19 variants will be quarantined while those with fake Covid-19 certificates face custodial sentences.
"As we continue to fight the Covid-19 pandemic, I call upon the whole nation to continue observing the WHO protocols, as well as to embrace the free vaccination program that is availed by government, to protect all our people," Mnangagwa said.
The additional measures came after the government last week deferred the re-opening of schools by two weeks due to rising cases.
As of Monday, Zimbabwe had recorded 47,284 Covid-19 cases, with 37,949 recoveries and 1,749 deaths.
Mnangagwa said a Covid-19 vaccination blitz will be rolled out in high-risk areas, including border towns and cities, tobacco auction floors, grain and cotton marketing depots, people's markets.