The UN Office for the Co-ordination of Humanitarian Affairs (OCHA) said the toll from the disease, which is normally easy to prevent and treat, had risen to 783 and that 16,403 people were believed to be infected.
But, despite growing international concern, Mugabe said in a nationwide televised speech "there is no cholera" in Zimbabwe.
"I am happy to say our doctors have been assisted by others and the WHO [World Health Organisation] ... so now that there is no cholera," he said.
He said that Western powers were using the disease as an excuse for intervening in the country.
"There is no cause for war any more ... The cholera cause doesn't exist any more."
'Under control'
Asked about Mugabe's remarks, Elisabeth Byrs, an OCHA spokesperson in Geneva, said: "The figures speak for themselves. We hope that the joint efforts of the United Nations and government will contribute to halting the epidemic."
Bright Matonga, a spokesman for the Zimbabwean government, told Al Jazeera: "I don't think its correct to say that he denied [that there was cholera], basically what he said is that the situation is now under control."
"We've received a lot of aid from all over the world assisting Zimbabwe with the cholera outbreak," he said.
Asked if he accepted the UN figures for deaths from cholera in his country, Matonga said: "I don't think it's a question of numbers.
"We've got an outbreak of the disease which needs to be controlled. We need clean water, we need chemicals, we need a lot of support ... it would be very unfortunate if people start politicising the issue of cholera."
But Peter Muturedzanwa, an aid worker for Oxfam, in the Zimbabwean capital Harare said the situation was still worsening.
"With the current food crisis, the cholera impact is going to cause a lot of suffering for Zimbabweans," he said.
"The rains are not promising to come, cholera is increasing, there is no food in shops. The situation is pathetic."
He said it was difficult to understand on what information the government was basing its claims on considering that most of the country's hospitals and clinics were not operating.
Outbreak spreads
South African officials have declared a stretch of the border area with Zimbabwe to be a disaster zone because of the increase in cholera cases.
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The UN said the toll from cholera had
risen to nearly 800 people [EPA] |
"The provincial government took a decision that the whole of the Vhembe district should be declared a disaster area," Mogale Nchabeleng, the northern Limpopo provincial government spokesman, said.
He said the disaster status would free-up funding and focus relief efforts in the district which includes the South African and Zimbabwean border towns of Musina and Beitbridge and the border crossing.
"Extraordinary measures are needed to deal with the situation," Nchabeleng said.
Farid Abul Kadir, the South African disaster management co-ordinator with the International Red Cross, told Al Jazeera: "Extraordinary measures include upscaling on social mobilisation, educating the public in prevention measures, purification of water, beefing-up security personnel, equipment and medical supplies.
"The [South African] government has put systems in place including health personnel and [health] messages the Red Cross has been able to provide ... so whoever is in the side of South African is being provided with the knowledge and also the cholera cases are being handled by the healthy ministry system that has been set in place."