“Switzerland is definitely not a safe haven for criminals nor terrorists, and the country’s banking secrecy system provides no protection for such people,” Villiger said at a news conference, adding that one bank account possibly linked to the US terror attacks had been frozen in a Swiss investigation. However, he said, “the measures taken so far…have revealed no indication that Osama bin Laden (the United States’ prime suspect) and his terrorist organisation have any funds in this country."

Earlier in the week, Switzerland had joined financial market regulators around the world in exchanging information surrounding the terror attacks. Regulators are investigating suspected short selling by associates of the terrorists in the weeks before the attack took place.

Other consequences of the attacks for Switzerland are mixed: while the Swiss franc has shot up as investors seek shelter in the traditional safe home during times of trouble, Swiss airline and insurance companies are suffering like their peers around the world.

Zurich-based Swiss Re said it faced an after-tax burden of around SFr2 billion ($1.25 billion) as a result of the attacks in America, up from previous estimates of SFr1.2 billion due to damage to buildings adjacent to the World Trade Centre.

Swiss Re says its estimates are based on the assumptions that claims will be paid in full. Given the complex circumstances surrounding the event, the outcome of ongoing substantial debate over liability and other issues will affect the ultimate amount paid by the industry. The company said its exposure comes largely from property and business interruption lines. Swiss Re is one of the lead reinsurers on the World Trade Center "Twin Tower" property and business interruption cover.

Swissair has bigger problems, and pressure mounted in Switzerland on the government, and even the banks to help the company to survive. Mr Villiger said on Friday that the government might help Swissair by taking a subsidiary part in a capital increase. The government has a three per cent stake in the Swissair Group and Villiger said any state intervention would have to correspond to that interest. On Saturday he attended an emergency meeting with Moritz Leuenberger, President of Switzerland, and Mario Corti, Swissair chairman, to discuss ways of recapitalising the airline.

Earlier in the month Swissair announced plans to raise airline ticket prices in a bid to reduce net debt and turn the troubled company around after it suffered a first half loss of SFr234 million ($140 million). The group said at the time it would shed 1,250 jobs out of 72,000 and planned to dispose of assets such as Nuance, its chain of airport retailers, ground-handler Swissport, and its 49.5% stake in Germany’s LTU Group, which had been largely responsible for the first half loss.

Swissair said on Thursday that it had lost about SFr65 million in the previous week. Swissair spokesman Rainer Meier said bankruptcy was “out of the question”, but leading Swiss aviation journalist Sepp Moser was quoted as saying that the group was “on the verge of collapse”. On Sunday UBS and Credit Suisse, the country's two biggest banks, said they would support a Swissair rescue. UBS, which did not participate in an earlier SFr1bn standby loan to Swissair, said that it would support Swissair in "working out a solution to building an adequate capital base".

Despite these domestic business problems, the Swiss franc surged higher on Friday to a 20-month high against the US dollar and an all-time peak against the euro. "Escaping risk is the main interest of traders at the moment," said Kit Juckes, chief strategist at Royal Bank of Scotland Financial Markets. "This has been reflected in the rise of the Swiss franc but also the fall in emerging market currencies."