Zimbabwe’s former President Mugabe, 94, is unable to walk because of ill health, President Emmerson Mnangagwa has said.
Mr Mugabe has been in Singapore for treatment for an undisclosed illness for the past two months, he added.
The former president also made several medical trips there towards the end of his time in power.
Mr Mnangagwa became head of state a year ago after Mr Mugabe was ousted following the intervention of the army.
Up to that point, Mr Mugabe had been in power for 37 years, first as prime minister, then as president.
He led the movement for Zimbabwean independence from white minority rule.