Zimbabwe's opposition leader Morgan Tsvangirai has said he will contest a presidential run-off, despite fears of widespread poll violence.
Speaking in South Africa, he said people would feel "betrayed" if he did not run, and vowed to return shortly.
Mr Tsvangirai called for an end to violence, as well as full access by international monitors and media.
Official first-round results put him ahead of President Robert Mugabe, but not by enough votes to win outright.
Mr Tsvangirai had earlier insisted he had secured more than 50% of the vote, and that there was therefore no need for a second round.
On Saturday, he told reporters that his Movement for Democratic Change (MDC) had faced a "very difficult" decision but that after consulting supporters in Zimbabwe, it had decided to take part.
"I am ready, and the people are ready for the final round," he said.
The opposition leader went on to demand "unfettered access of all international observers" and journalists covering the vote.
He also called for the deployment of southern African peacekeepers to curtail any violence.
The BBC's Peter Greste in Johannesburg says the announcement was not a big surprise, as boycotting the poll would have meant handing victory to President Mugabe by default.
Our correspondent says Mr Tsvangirai has to get home soon - as long as he remains outside Zimbabwe, it will be hard to maintain the support he needs to win the run-off.
The MDC leader said he expected to return to Zimbabwe in the next two days.
Source: BBC NEWS


