The Archbishops of Canterbury and York have joined international church leaders in declaring this Sunday a special "day of prayer" for Zimbabwe.

In a joint statement, Dr Rowan Williams and Dr John Sentamu called for Christians worldwide to pray for an end to the "mayhem" in Zimbabwe

Their intervention comes after the country's own church leaders earlier this week warned that violence in Zimbabwe will reach full-scale genocide if the international community doesn’t intervene.

In a joint statement, Zimbabwe's Catholic, Anglican and evangelical church leaders warned that violence following the elections last month would turn to genocide as bad as that of Rwanda if the world failed to act.

“We warn that if nothing is done to help the people of Zimbabwe from their predicament, we shall soon be witnessing genocide similar to that experienced in Kenya, Rwanda, Burundi and other hot spots in Africa and elsewhere,” they said.

Dr Williams and Dr Sentamu echoed their concerns, warning that without help, the continuing political violence "could unleash spiralling communal violence" as has happened elsewhere in Africa.

The Church of England's two senior Archbishops said: “The current climate of political intimidation, violence, vote rigging and delay has left the presidential election process without credibility. Now the people of Zimbabwe are left even more vulnerable to conflict heaped upon poverty and the threat of national disintegration.”

The average life expectancy of Zimbabweans hovers around 35, lower than any war zone. Since 1994 it has fallen from 57 to 34 for women and from 54 to 37 for men.

Zimbabwe has the highest proportion of orphans in the world,1.3 million, largely due to the devastation caused by HIV and Aids. Aids-related illnesses kill 3,200 people each week