zimbabwe’s tragedy continues. The mystery is why the one man who holds the key to bringing the agony to an end, still refuses to act decisively. South Africa’s President Thabo Mbeki continues to insist that only negotiations can end the impasse between Robert Mugabe’s ZANU-PF and the MDC of Morgan Tsvangirai.

There was a point just after the original elections in March when the South African leader’s cautious approach seemed to have merit. There were too many voices, not least from the UK, the former colonial power in Zimbabwe, clamoring for Mugabe to go. Mugabe could, with a degree of justice, claim that the British have never forgiven him for depriving white farmers — almost all of British origin — of their farms. Therefore the attacks on him carried an element of revenge.

But after the farce of the long-delayed presidential result and the murder, thuggery and intimidation that surrounded the second round of the presidential election, Mugabe’s political position became much less tenable. He did not help his cause by pronouncing before the second round vote that nobody could remove him from the presidency. In the face of that sort of intransigence and the certainty that the second round result would again be fixed plus the growing toll of death and injury among his MDC supporters, Tsvangirai quit the race.

Tsvangirai had looked to the meditation by the Southern Africa Development Community (SADC) whose Zimbabwe mission is led by Mbeki. But as the mediators appeared to be getting nowhere, Tsvangirai has become openly critical of the South African president’s role and has demanded he step down.

Mbeki shows no sign of doing so. Indeed last night he flew to Zimbabwe’s capital Harare for “urgent” talks with Mugabe and a splinter group of the MDC. He arrived 24 hours after Mugabe announced that the precondition for talks on a national unity government would be the acceptance of him as a legitimate president. The 84-year-old Zimbabwean leader could not have made it plainer that he is not in reality going to budge.

If Mbeki’s message to Mugabe last night was that the economic aid, the unpaid-for fuel and electricity provided to Zimbabwe by South Africa were going to stop, unless the old man abandons power and retires gracefully, then he will have earned respect in the last part of his own rather undistinguished presidency. But Mbeki seems hooked on a piece of history which while significant is no longer relevant. Mugabe was a successful liberation fighter who overthrew white rule in the then Rhodesia and also offered valuable support to the ANC in its struggle against apartheid South Africa. For this he has been revered.

But time has moved on. Since Mugabe’s rule began in 1980, the economy has collapsed because of his government’s corruption and ineptitude. British-led international sanctions since 2002 have not helped but Zimbabwe’s finances were collapsing long before. The country desperately needs change, new leadership and new hope. For the sake of Zimbabweans, Mbeki must abandon his old friend.