A money-laundering case against Asif Ali Zardari, the man poised to take over as Pakistan’s next president, has been dropped by a Swiss court, leading to the release of millions of pounds — and renewed questions about where Mr Zardari acquired such wealth.

The case was closed and $60 million (£33 million) handed back to Mr Zardari after the Pakistani Government withdrew its requests for judicial assistance from Switzerland and said it had no claim on his assets. It said that he had not done anything illegal and that the charges had been politically motivated.

The decision may enrich Mr Zardari, the widower of Benazir Bhutto and frontrunner to replace Pervez Musharraf in elections next month, but it also embroils him in renewed controversy about his financial dealings.

His contested accounts were frozen in 1997 at the request of Pakistani authorities investigating allegations that Mr Zardari had received kickbacks and commissions on deals with foreign companies while a minister in his wife’s second government. The withdrawal of the case by Pakistan’s Government — led by Mr Zardari’s Pakistan People’s Party (PPP) — raised more questions about the eligibility of a politician dubbed “Mr Ten Per Cent” to hold the country’s top office.

Under the Pakistani constitution a presidential candidate has to declare all assets inside and outside the country and the taxes paid on them. Opponents demanded that Mr Zardari reveal where he had obtained the $60 million and his other assets.

Mr Zardari will rely on a pliant judiciary to keep him from being disqualified for the elections. This, his political rivals claim, is why he is reluctant to restore the independent-minded judges sacked by Mr Musharraf under emergency rule last year.

Judicial authorities in Geneva have been investigating allegations since 1997 that Mr Zardari took kickbacks from Swiss cargo inspection companies and channeled some $12 million via offshore companies into Swiss bank accounts. Pakistan had asked the Swiss authorities to block further funds, totalling $60 million.

Mr Zardari has always denied the charges, calling them politically motivated, but he and Ms Bhutto were convicted by a Geneva court in 2003 of laundering kickbacks. That verdict was thrown out on appeal, sparking a wider probe by an investigating judge.

Daniel Devaud, the Swiss magistrate who brought charges in 1998 against Zardari and Bhutto, then Pakistan’s Prime Minister, said the probe should have continued.

“Politely put, it is hard to say there was nothing in the files to indicate corruption,” he said.

Farooq Naik, the federal law minister who is also Mr Zardari’s lawyer, neither confirmed nor denied that the assets belonged to Mr Zardari. “The documents I have seen do not show that the accounts were in the name of Mr Zardari,” Mr Naik said.

Doubts have also been raised about Mr Zardari’s readiness to become president after it was reported this week that he was suffering from dementia, depression and post-traumatic stress disorder as recently as last year.

The illnesses, diagnosed by two New York psychiatrists, were detailed in court documents used by Mr Zardari to delay attempts by the Pakistani Government to sue him for corruption in the English High Court.

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