South Africa's ruling party boss Jacob Zuma on Monday urged Zimbabwe's political leaders to quickly break a stalemate on a unity government, saying mediation could still solve the country's crisis.

Despite growing international calls for Zimbabwe President Robert Mugabe to step down, Zuma said he still supported the mediation effort led by former South African president Thabo Mbeki.

"We need some swift action to deal with the situation in Zimbabwe," Zuma said at the opening of talks in Windhoek with Namibian President Hifikepunye Pohamba.

"We fully support Mbeki's mediation efforts and we urge the Zimbabwe leadership to act and... pave the way for a unity government," Zuma added.

Mugabe and opposition leader Morgan Tsvangirai signed a unity accord on 15 September, but the deal has floundered amid disputes about how to divide control of key cabinet posts.

Zuma is on a one-day visit to Namibia to strengthen ties between his African National Congress (ANC) and Pohamba's ruling party.

AFP