In what could raise questions about his ability to rule Pakistan, a newspaper has claimed that Asif Ali Zardari, the country's leading contender for presidency, was suffering from severe mental problems as recently as last year.

Zardari was diagnosed with a range of psychiatric illnesses, including dementia, post-traumatic stress disorder and major depressive disorder, the Financial Times reported, citing court documents filed by his doctors.

In fact, his illnesses were said to be linked to the fact that he spent 11 of the past 20 years in Pakistani prisons fighting corruption allegations, during which he also claims to have been tortured, the report said.

According to the documents, Philip Saltiel, a New York- based psychiatrist, found in March 2007 that Zardari's detention had left him suffering from "emotional instability" and memory and concentration problems. "I do not foresee any improvement in these issues for at least a year," he wrote.

Stephen Reich, another psychologist, had said Zardari was unable to remember even birthdays of his wife and children, was persistently apprehensive and had thought about suicide.

Moreover, the documents revealed that Zardari used the medical diagnosis to argue successfully for the postponement of a now-defunct English High Court case in which Pakistan's government was suing him over alleged corruption.

The case, brought to seize some of his assets in the United Kingdom, was dropped in March, at about the same time that corruption charges in Pakistan were also dismissed.

Though Zardari was not available to comment, Pakistani High Commissioner to Britain Wajid Shamsul Hasan said the PPP chief was now fit and well.

Hasan, a long-time friend of the Bhutto family, told the paper that Zardari had subsequent medical examinations and his doctors had "declared him medically fit to run for political office and free of any symptoms".