Western hostility towards Zimbabwe is deterring investment, despite President Emmerson Mnangagwa's previous efforts to woo Western governments.
Zimbabwean soldiers ordered shopkeepers to close and leave the centre of Harare, the day after deadly clashes broke out.
Zimbabwean soldiers walked the streets of Harare as calm returned a day after deadly clashes between security forces and opposition protesters.
Mathole Motshekga said he suspected prosecutors had delayed taking action over the case for political reasons.
The "military government" that has taken power in Zimbabwe must be removed or the country could descend into chaos, an exiled Mugabe loyalist said.
An investigation found that Trillian had been paid R495m by Eskom despite carrying out no work.
Leaked emails and documents alleging improper dealings in state contracts opened President Jacob Zuma up to renewed scrutiny and may deepen ANC divisions.