Morgan Tsvangirai during news conference in Pretoria, 10 May 2008

Zimbabwean opposition leader Morgan Tsvangirai says he will take part in a presidential runoff against the incumbent, Robert Mugabe.

Tsvangirai made the announcement in Pretoria, South Africa Saturday but also laid out several conditions. He called for the cessation of all violence, the presence of South African Development Community peacekeepers and access for international observers and media.

The leader of the opposition Movement for Democratic Change said he will return home soon and that the runoff should take place no later than May 24.

Tsvangirai maintains he won an outright victory in the March 29 presidential election. The electoral commission says while he won the most votes, he fell short of a majority

Under Zimbabwean electoral law a runoff should be held within 21 days of when the initial results were announced, May 2.

Authorities have not set a date for the runoff.

In the March elections, Mr. Mugabe's ZANU-PF party lost its majority in parliament for the first time in 28 years.

South African President Thabo Mbeki traveled to Zimbabwe Friday and met with President Mugabe. He did not meet with the opposition, which has criticized Mr. Mbeki for refusing to take a tough line on President Mugabe.

The opposition and human rights groups accuse Mugabe loyalists are trying to intimidate MDC supporters ahead of a runoff election.

Some information for this report was provided by AFP, and Reuters.