Late on Friday Belgian police searched both the private home and official residence of Mr Claes, who has been linked to a kick-back scandal. Mr Claes, who cuts a fine figure in a white tie, had been conducting an orchestra in the town of Sint Niklaas before he returned to his home on Friday.
He gave permission for his home and residence to be searched, and said that police did not take any documents. But they did note down his bank account numbers, he said. Mr Claes has not used his diplomatic immunity to obstruct the investigation and has said that he wants to co-operate as fully as possible with investigations. Last week the Belgian parliament agreed that he could be questioned by the country's top court, and Mr Claes said he hoped this would lift any remaining suspicion.
The Italian helicopter company Agusta is alleged to have paid £1m to the Flemish Socialist Party to secure a contract with the Belgian Army in 1988. Mr Claes, who was then economic affairs minister, has admitted that he was told of an alleged offer of cash but says that he advised that it be turned down.
Senior US and British officials at Nato say they have full confidence in Mr Claes.
But the alliance is increasingly bogged down in complex disputes between member states, and the time that Mr Claes is spending dealing with the allegations is clearly distracting him from his work.
There is growing speculation that Nato capitals are preparing for the possibility that Mr Claes may have to step down.Reuse content