Tutu, the South African Nobel Peace Prize laureate, urged the 84-year-old Mugabe to accept that he lost last month's presidential election. Election results have yet to be released amid the potential of violence between political parties and a blighted economy.
Food and fuel are in short supply in Zimbabwe while the country's inflation rate is more than 100,000 percent - the world's worst - and unemployment is above 80 per cent. Millions have fled the country, mostly to South Africa.
"They are tipping over the precipice," Tutu told a small group of reporters. "Violence is very much in the air.
"I would have hoped there would be a great deal more pressure, not just from South Africa but from the international community," he continued. "On the whole, African leadership has not done themselves proud on this one."
The Anglican Archbishop said international peacekeeping troops may be needed to help restore order in Zimbabwe and the country's economy could benefit from a "mini-Marshall Plan" orchestrated by foreign governments.
The Marshall Plan was a US aid initiative after World War II to rebuild Europe's economy.
His critics accuse Mugabe, who led the fight against white-minority rule in the former Rhodesia, of reducing a once-prosperous nation to misery.
Zimbabwe's opposition accuses Mugabe of unleashing a campaign of violence since elections and called on African states to intervene to prevent bloodshed.
Movement for Democratic Change leader Morgan Tsvangirai says he won the March 29 vote.
