Moyo, a former army general who announced the military coup that led to the removal of the late long-serving leader Robert Mugabe in November 2017. Moyo died at a local hospital early on Wednesday, Charamba said.
"The nation will be kept apprised of further developments regarding this untimely demise of the late minister, himself a decorated soldier and freedom fighter," Charamba said.
Moyo was one of several generals who, after helping plot the coup, were rewarded with senior positions in President Emmerson Mnangagwa's cabinet and the ruling ZANU-PF party.
Another cabinet minister, retired general and agriculture minister Perrance Shiri, died of the virus last July.
Zimbabwe has suffered a surge in COVID-19 infections, with more than half of the 28,675 total cases and 825 deaths being recorded since New Year's Day. (Reporting by MacDonald Dzirutwe; Editing by Emma Rumney and Timothy Heritage)
epa08123232 Chinese Foreign Minister Wang Yi (L) and shakes hands with the Zimbabwean Foreign Affairs and International Trade Minister, Sibusiso Moyo (R) during a press conference in Harare, Zimbabwe, 12 January 2020. Wang Yi is in the country for a three-day visit as part of a five-nation tour that will also take him to Egypt, Djibouti, Eritrea, and Burundi. EPA-EFE/AARON UFUMELI