African Union chief Jean Ping said on Wednesday he has been assured by that round two of Zimbabwe's presidential elections will unfold "in peace and transparency".

Speaking during a meeting of the African Union's executive council in Tanzania's capital Arusha, Ping recalled his trip to southern Africa earlier this week, including the Zimbabwean capital Harare.

"We met not only with President Robert Mugabe, but also with presidents Mbeki and Mannawasa," he said, referring to South African leader Thabo Mbeki and Zambian counterpart Levi Mwanawasa.

"The assurances given to me were that the second round would take place in peace and transparency," he told a press conference.

Ping, former deputy prime minister and foreign minister of Gabon, made his remarks as the African Union, at its Addis Ababa headquarters, appealed for a free, transparent and non-violent runoff.

"In the run-up to the second round of the presidential poll, the AU re-emphasises the need for Zimbabwe to implement the conditions set out in the Declaration on the Principles Governing Democratic Elections in Africa," it said in a statement received by AFP in the Ethiopian capital.

The pan-African organisation urged "all the Zimbabwe political actors to conduct their activities in a free, transparent, tolerant, and non-violent manner to enable eligible Zimbabweans exercise their democratic rights."

"It is essential also that peace and security be maintained, and that the will of the people be respected by all stakeholders once the results are announced," the statement went on.

Results announced by Zimbabwe's electoral commission almost five weeks after the 29 March general polls indicate that opposition candidate Morgan Tsvangirai led President Robert Mugabe in the first round.

Yet his margin was not sufficient to avoid a run-off. Tsvangirai and the Movement for Democratic Change (MDC) insist they won the presidential ballot outright in the first round.

The country's electoral commission, which the MDC has consistently accused of being biased, is yet to announce the date for a second round. Mugabe himself has made no comment about his intentions regarding the run-off.