Pakistani President Asif Ali Zardari is being treated in Dubai for a heart condition, his spokesman has said, dismissing reports that he may resign. A presidential spokesman said that Mr Zardari was undergoing "medical tests and check-ups as planned". But his departure has fuelled speculation in the Pakistani media that he may be on the verge of resigning. A controversial political figure, he came to power after his Pakistan People's party won polls in 2008. The party had been led by his wife, former Pakistani prime minister Benazir Bhutto, who was assassinated in 2007. "President Asif Ali Zardari is in a Dubai hospital for medical tests and checkup as planned," presidential aide Farhatullah Babar told Reuters news agency. "Reports in some sections of the media speculating on the president's activities and engagements are speculative, imaginary and untrue," he added. The Pakistani civilian government has been under pressure in recent weeks after a scandal, which resulted in the resignation of Pakistan's envoy to the US, over a leaked memo in which officials allegedly sought US help against a possible military coup.