Pressure was mounting last night for the key role of mediating an end to the crisis in Zimbabwe to be taken out of the hands of Thabo Mbeki, the President of South Africa, whose “softly softly” approach to Robert Mugabe has been condemned worldwide.

The UN’s push for greater involvement came amid mounting frustration with the failure of current mediation efforts. The United States pushed for Mr Mugabe and other ring-leaders of election abuses in Zimbabwe to be slapped with a worldwide travel ban and the freezing of their assets.

Diplomats said that the UN was considering a shortlist of leading African politicians, including the former UN Secretary-General, Kofi Annan, to help negotiate a political settlement in the country.

Other possible mediators include the former Nigerian President, Olusegun Obasanjo; the former President of Mozambique, Joaquim Chissano; and President John Kufuor of Ghana.

At a meeting in Egypt on Monday, the African Union stopped short of condemning the fraudulent re-election of Mr Mugabe but approved a resolution calling on him to negotiate with Morgan Tsvangirai, the opposition leader, who pulled out of the run-off poll after a campaign of violence against him and his supporters.

Mr Mugabe returned to Zimbabwe yesterday aware that even neighbours such as Botswana, which publicly urged his expulsion from the AU, were turning against him. Mr Tsvangirai kept up the pressure on the international community. He again rejected the AU decision to keep Mr Mbeki, who is the official mediator of the Southern African Development Community (SADC), in sole charge of efforts to resolve the political crisis.

Speaking to reporters at his home in Harare, Mr Tsvangirai said that the Opposition would not participate in talks unless an additional mediator was appointed. “Our reservations about the mediation process under President Mbeki are well known,” said Mr Tsvangirai, who leads the opposition Movement for Democratic Change (MDC), which just failed to win an outright victory in a first poll.

“Unless the mediation mechanism is changed, no meaningful progress can be made toward resolving the Zimbabwe crisis,” he said.

Mr Mbeki, 66, dispatched some of his closest advisers to Harare to push for talks. South Africa has yet to recognise Mr Mugabe’s re-election but has distanced itself from the European Union’s condemnation of the poll. Mr Mugabe, who has frequently pulled the wool over the eyes of Mr Mbeki, will have a harder time from a United Nations or African Union-led team.

Diplomats say that the UN Secretary-General, Ban Ki Moon, plans to discuss the possible appointment of a new mediator with Mr Mbeki when both men are in Japan next week for the G8 summit. He will also consult Jakaya Kikwete, the Tanzanian President and the AU’s current chairman.

As the search for a new mediator intensified, US diplomats circulated a proposed blacklist of 12 names as an annexe to a proposed resolution that would take the symbolic step of imposing sanctions on Zimbabwe for the first time since independence in 1980.

Mr Mugabe is named as the “head of government responsible for activities that seriously undermine democracy, repress human rights and disrespect the rule of law”. Constantine Chiwenga, the commander of the Zimbabwean Army; Augustine Chihuri, the police chief; Perence Shiri, the head of the air force; and Gideon Gono, the central bank governor, are named on the list, circulated by the United States.

Also included are Patrick Chinamasa, the Justice Minister; George Charamba, Mr Mugabe’s spokesman; Emmerson Mnangagwa, the Rural Housing Minister; and Happyton Bonyongwe, the chief of the Central Intelligence Organisation.

US diplomats held more talks in New York last night to round up the votes necessary for adoption of the resolution by the 15-nation council, possibly next week.

South Africa, Russia and China oppose the sanctions and are backed by Libya, Vietnam and Indonesia. Burkina Faso is the key ninth vote needed by the Western bloc. A Western diplomat said yesterday that Burkina Faso was “holding up well”. The resolution will be adopted if it is backed by the necessary nine votes, unless it is vetoed by China or, less likely, Russia.

A diplomat from a country that opposes the resolution predicted that China would be reluctant to cast its veto because of the Olympics.

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