Harare - Zimbabwe's main opposition leader Morgan Tsvangirai has taken ill and is in South Africa for medical treatment, officials say.Tsvangirai, 64, underwent an operation on Wednesday, according to a statement from Movement for Democratic Change (MDC) secretary general Douglas Mwonzora.It was still not clear what he was suffering from and his party had not said which hospital he was being treated in.Mwonzora insisted that he was now "recovering"."After the procedure, he’s recovering in the hospital. They’re expecting to discharge him within the next three days. It's nothing incurable," Mwonzora told News24.Like his rival President Robert Mugabe, Tsvangirai's health has been a topic of speculation for some time. He was hospitalised in an upmarket clinic in Harare in 2014, allegedly for flu.First familyNews that Tsvangirai, who has led the MDC since it was founded in 1999, has had to travel outside the country for treatment will raise some eyebrows.The opposition has been critical of the first family's insistence on seeking medical care in Singapore and Dubai.Mugabe's daughter Bona last month chose not to have her first baby in Zimbabwe, instead travelling with her mother to Dubai.Mwonzora said Tsvangirai's doctor in Zimbabwe had told him to go to South Africa because "the facility in question was not available locally".The Zimbabwe Medical Association, which groups doctors from the private and public sector, reported on May 9, that Harare's main Parirenyatwa Hospital had no running water and staff were "carrying water for patient care in buckets". Water supplies were later reported to have been restored.Private hospital treatment in Zimbabwe is in some cases more expensive than in neighbouring South Africa.