The death toll from cholera in Zimbabwe has risen to 978, with 18,413 suspected cases, the UN Office for the Co-ordination of Humanitarian Affairs said in Geneva.
In Zimbabwe, the justice minister Patrick Chinamasa told the state's Herald newspaper that the government had evidence Botswana was giving military training to members of Morgan Tsvangirai's opposition Movement for Democratic Change (MDC) as part of a plot to remove President Robert Mugabe. Botswana's President Ian Khama is among the few African leaders to publicly criticise Mr Mugabe.
He has called for new elections after Mr Mugabe and Mr Tsvangirai reached deadlock over posts in a shared administration. Botswana's foreign ministry said in a statement that Zimbabwe had failed to produce any tangible facts to support the allegations. Zimbabwe's opposition dismissed the accusations.
The justice minister said: "Botswana has availed its territory, material and logistical support to MDC-T for the recruitment and military training of youths for the eventual destabilisation of the country with a view of effecting illegal regime change.
We now have evidence that while they [MDC] were talking peace they have been preparing for war and insurgency, as well as soliciting the West to invade our country on the pretext of things like cholera."
The epidemic and Zimbabwe's economic meltdown have drawn new calls from Mr Mugabe's Western foes for the resignation of the 84-year-old leader, who has ruled since independence in 1980.