Mugabe, who has been ruling the country since 1980, is said to be confined to his home in Harare while unconfirmed reports say his wife Grace, who was bidding to succeed him as president, has fled to Namibia.
The military’s action followed the sacking of Vice-President Emmerson Mnangagwa, a fierce rival of Mrs Mugabe.
It is believed that negotiations are ongoing for Mr. Mnangagwa to take over from Mr. Mugabe, who is 93.
In a statement on the development, Mr. Rawlings said: “As unavoidable as the Zimbabwe situation may be, let us hope that the transition occurs without destroying Mugabe’s legacy and dignity unduly. His African pride, dignity and audacity were unassailable. He served and lived for the dignity of his fellow black in a manner that so many of us fell very short of”.