Battling an acute shortage of cash in the country, which is nearly in its third consecutive year, companies have had to turn to the parallel market to access the scarce United States dollar for payments of raw materials and to also settle their dues to debtors outside the country.
On Saturday, President Mnangagwa announced that the polls would be held in July.
Mugabe and his wife told reporters at their Harare mansion that they adhered to the amnesty, according to Times Live.
Companies and individuals cited under Category Three included ruling party official and former civil servant Elias Musakwa who allegedly externalised US$9 million to Portugal and gold miner Metallon which is said to have stashed away over US$25 million in a bank account in Botswana.
"Baba (father) did not want to put pen to paper, in fact it was me who urged him to resign for the sake of peace because Baba did not want to", Grace Mugabe said, in comments carried by the private NewsDay.
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It was Mugabe's first public statement since his resignation previous year.
"We must undo this disgrace which we have imposed on ourselves, we don't deserve it. Zimbabwe doesn't deserve it".
"I say it was a coup d'etat - some people have refused to call it a coup d'etat", Mugabe, 94, told South Africa's SABC broadcaster, referring to the brief army takeover which led to Mnangagwa assuming power after Mugabe's resignation.
Mnangagwa has said at various forums that "Zimbabwe is open for business" as he seeks to revive an economy that was ruined under Mugabe's near four-decade rule.
"Noting elections are first and foremost for Zimbabweans, Mr Steiner welcomed President Mnangagwa's election pledge for a credible and peaceful election as an important milestone for a successful transition", the statement said. The views of users published on Bulawayo24 are therefore their own and do not necessarily represent the views of Bulawayo24.