By Peter Fabricius and Chiara Carter
In a dramatic, last-minute intervention, President Thabo Mbeki has halted an African Union invasion this weekend of the tiny Comoros island of Anjoun as troops gathered on a neighbouring island, ready to overthrow Anjouan's ruler.
It is reliably understood that Mbeki spoke to the head of the African Union, Tanzanian President Jakaya Kikwete, by phone on Friday to stall the attack, intended to depose President Mohamed Bacar.
For some time South Africa has been involved in efforts to resolve the situation and these were renewed after the department of foreign affairs received a letter this week from Bacar, whose offence seems to be that he overstayed in office for two months last year.
Pretoria is now engaged in efforts to make the suspension of the invasion stick and find lasting peace.
While many African tyrants have clung to power for decades with impunity - Zimbabwe's President Robert Mugabe stands for re-election on March 29 to try to extend his rule to 33 years - this extraordinary plan was to be the AU's first military invasion of a member country.
An AU force was assembling on the nearby island of Moheli - apparently with French help - ready to cross the narrow channel to Anjouan to help the federal government of Comoros get rid of the island's "rebel" leader, Bacar.
Anjouan, population 250 000, size 42km2, is one of three semi-autonomous islands in the federal Comoros state. It is the richest island.
In the AU force preparing to invade Anjouan were contingents from two undemocratic countries, Sudan and Libya, as well as elements from democratic Senegal and Tanzania.
The federal government of Comoros and the AU insist that Bacar's government is illegitimate because he came to power last year in an election that the federal constitutional court deemed illegal.
Bacar retorts that his arch-rival, federal President Ahmed Sambi, packed the court with his own supporters so that its verdict was unjust.
The precise rights and wrongs of the election are fuzzy enough for South African officials to believe that the drastic solution of a military invasion is unwarranted. Bacar did not defy a constitutional limit on running for a second term because there is no such limit. His offence was to remain in office after his term expired in April until the election in June.
On Wednesday, after Aziz Pahad, the deputy foreign minister, had said his government supported the invasion politically, Mbeki told journalists in Mauritius that a military attack was unnecessary because Bacar had written to the South African government, agreeing to run new elections in May.
On Friday, Bernard Membe, Tanzania's foreign minister, had declared that military intervention was irreversible, adding that Bacar had squandered many chances for a negotiated settlement.
"He is a liar," he said about Bacar's latest offer.
Chrysantus Ayangafac of the Pretoria-based Institute for Security Studies (ISS) said the military build-up and sabre rattling from the AU might be diplomatic brinkmanship designed to scare Bacar into surrendering power. But Bacar has vowed to fight to the death.
Questions are also being asked about South Africa's role. Nkosazana Dlamini-Zuma, the foreign minister, headed a group of regional countries that had been trying for months to resolve the conflict. She was supposed to lead a mission to the Comoros late last month to discuss the crisis, but cancelled the mission.
Some diplomats believe she might have called it off because she realised the AU had already determined to seek a military solution.
Some analysts say the decades of upheaval in Comoros, which has experienced 19 coups or coup attempts since independence from France in 1975 - many of them engineered by the late French mercenary Bob Denard - have made the AU impatient of negotiations.
Jakkie Cilliers, the ISS director, said the AU decision was technically legitimate under the AU charter as it has been sanctioned by the union's peace and security council, and it would be intervening at the invitation of the federal Comoros government to help it overturn a unconstitutional transfer (or in this case, retention) of power in Anjouan.