Russia previously announced that Lemekhani Nyirenda had been killed on the battlefield in Ukraine in September, prompting Zambia to ask how he had ended up fighting in the war.
Kakubo said Russia's Foreign Affairs Minister Sergei Lavrov told him by telephone that Nyirenda was pardoned on Aug. 23 to join the military operation, in exchange for an amnesty.
"We were informed that Russia allows for prisoners to be provided an opportunity for pardon in exchange for participation in the special military operation," Kakubo said.
According to Nyirenda's father, he had been serving a nine-year jail sentence on the outskirts of Moscow for a drug offence when he was "conscripted" to fight.
Kakubo said Nyirenda's remains had arrived in Moscow on Friday and were expected in Zambia on Sunday.
Russia has also informed Zambia that money owed to Nyirenda, together with all the documentation relating to his amnesty, recruitment and death, would be handed to a Zambian representative who would accompany the body, the minister said.
Russian businessman Yevgeny Prigozhin, a close ally of President Vladimir Putin, said last month the Zambian student had been fighting for his Wagner Private Military Group.
The Wagner group has launched large recruitment drives in Russian prisons, looking to send more fighters into Ukraine to support the faltering Russian invasion.
(Reporting by Chris Mfula; Editing by Bhargav Acharya and Crispian Balmer)
