ISLAMABAD,Pakistan - Pakistani President Asif Ali Zardari is in Dubai for treatment for a heart condition, the government said on Wednesday, with one source saying he had suffered a minor heart attack and fuelling speculation that the leader may resign.

Pakistan's President Asif Ali Zardari speaks to journalists at the Elysee Palace in Paris, in this file photo taken August 2, 2010. [Photo/Agencies]

The statement from the prime minister's office said Zardari went to a Dubai hospital at the insistence of his children, who live there. It contradicted earlier reports from Zardari's own office that the tests were scheduled and routine.      

"The president went to Dubai following symptoms related to his pre-existing heart condition," Prime Minister Yusuf Raza Gilani's media office said.

"The president will remain under observation and return to resume his normal functions as advised by the doctors."

A presidential spokesman later quoted Zardari's doctor as saying his condition was stable.

Outside the special ward at the American Hospital housing Zardari, Pakistani security guards and local officers guarded the area. Party members, diplomats and media milled about, waiting for word on his health.

A Pakistani source in Dubai familiar with the 56-year-old president's condition said that he had suffered a minor heart attack.

"Two days ago, he had chest pain" and decided to go to Dubai, the source said, adding that Zardari had suffered a minor heart attack six years ago.

"Since then, he has been on medication."

A Dubai-based member of Zardari's Pakistan People's Party (PPP), Mian Muneer Hans, said the president landed in Dubai around 7:30 pm on Tuesday.  

"He walked to his car in the airport and was not on any ambulance," said Hans, adding that he was accompanied by his doctor and petroleum minister Asim Hussain and taken straight to the American Hospital.  

"He's taking rest in the hospital now. He may be there for two to three days," he added.  

The hospital's chief executive officer Thomas Murray, contacted by Reuters, declined to comment on the reports.

The rumours about his health and possible resignation swirled on Twitter and other social media.

"Some elements blew up this to create unrest in the country," said Fauzia Wahab, a senior member of the PPP. "His visit to Dubai and having a medical check up is perfectly normal."