Mr Mugabe has defied calls for Friday's vote to be called off
Zimbabwe's President Robert Mugabe has vowed to press ahead with Friday's run-off presidential election despite growing international condemnation.
Speaking to supporters, he said London and Washington could "shout as loud as they like" but the vote would be held.
South Africa's governing ANC party has accused his government of "riding roughshod" over democracy, while the UN has said a fair poll is "impossible".
Zimbabwe's opposition has withdrawn from the poll amid mounting violence.
The Southern Africa Development Community (Sadc) regional bloc is due to hold an emergency summit on Wednesday on Zimbabwe's political crisis, reports said.
Zimbabwe's opposition Movement for Democratic Change, led by Morgan Tsvangirai, said it had confirmed in writing on Tuesday its withdrawal from the presidential race.
The MDC says some 86 supporters have been killed and 200,000 forced from their homes by Zanu-PF militias. The ruling Zanu-PF party blames the MDC for the violence.
Speaking at a rally in the town of Banket, Mr Mugabe said: "They can shout as loud as they like from Washington or from London or from any other quarter. Our people, our people, only our people will decide and nobody else."
We are deeply dismayed by the actions of the government of Zimbabwe which is riding roughshod over the hard-won democratic rights of the people of that country
He accused Mr Tsvangirai of pulling out of the election because he became frightened of losing when he saw "a political hurricane coming his way".
The UN Security Council on Monday unanimously agreed to condemn the violence in Zimbabwe and said a free and fair run-off election would be "impossible".
Tuesday saw a senior US state department official said Washington would not recognise the result of the vote because the opposition had been violently forced out of the running.
"People were being beaten and losing their lives just to exercise their right to vote for their leadership so we cannot, under these conditions, recognise the outcome if, in fact, this run-off goes forward," Assistant Secretary of State for African Affairs Jendayi Frazer told the BBC.
South Africa's governing ANC party added its voice to growing international criticism of Mr Mugabe's government on Tuesday.
It was "deeply dismayed by the actions of the Zimbabwean government - which is riding roughshod over hard-won democratic rights", the party said.
It referred to "compelling evidence of violence, intimidation and outright terror".
Former UN High Representative in Bosnia and Herzegovina Paddy Ashdown, a British politician, warned Zimbabwe's violence could descend into genocide like that in Rwanda in 1994
The International Cricket Council said it would consider whether to ban Zimbabwe from international cricket at a meeting in Dubai next week
An African election observer, who does not want to be named, told the BBC torture was "the order of the day" in Zimbabwe
A BBC reporter in Bulawayo, south-west of Harare, reported that members of an MDC faction had this week been ambushing and attacking pro-Zanu-PF so-called war veterans in the area
The MDC won the parliamentary vote in March, and claims to have won the first round of the presidential contest outright.
According to official results, Mr Tsvangirai was ahead of Mr Mugabe but failed to gain enough votes to avoid a run-off.
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