"Zimbabwe has collapsed… Former president Thabo Mbeki is compromised and no longer suitable for the mediation process," the National Church Leaders’ Consultation concluded after a two-day meeting in Stellenbosch in the Western Cape.
"SADC [Southern African Development Community] and the South African government have failed the people of Zimbabwe and the continent through their so-called quiet diplomacy.
"We respectfully call for the intervention of the African Union and the appointment of a new facilitator of the talks in Zimbabwe," the group of more than 30 church leaders said.
The group includes Catholic, Methodist, Anglican, Dutch Reformed, Lutheran and Rhema leaders.
Cardinal Wilfred Napier, Bishop Ivan Abrahams, Archbishop Thabo Makgoba, Pastor Ray McCauley and Eddie Makue of the South African Council of Churches were among those who supported the statement.
"We believe that Robert Mugabe is holding to illegitimate power. The people of Zimbabwe spoke on March 31, 2008 by electing a new leadership; we therefore call upon Robert Mugabe to resign in order to give democracy a new chance," the National Church Leaders said in a statement.
"We also call on churches, civil society groups and political leaders in southern Africa to urgently address the humanitarian crisis in Zimbabwe."
The leaders said they would "seek and facilitate the unity of the church in Zimbabwe", assist in providing food aid through church structures and "actively work for the downfall of unjust rule in Zimbabwe".
Turning to South Africa, the group called on political leaders to ensure peaceful general elections.
"We appeal to all South Africans to reject those who will cheapen the sanctity of life by resorting to violence in order to achieve their political objectives.
"We appeal to all political parties to abide by the electoral code of conduct and not to engage in campaigns characterised by name-calling, lies, threats of violence, bribery or corruption meant to influence election outcomes." – Sapa