Attacks on Switzerland are a form of "economic war" by rival nations who want to hurt the country’s status as a financial centre, UBS CEO Sergio Ermotti told Swiss newspaper SonntagsZeitung yesterday.

“Switzerland has been attacked since 2008. We are in the middle of an economic war," Ermotti was quoted as saying. "The goal is to weaken the financial centre of Switzerland."

"It's about weakening the two big Swiss banks which are internationally successful... Not only foreign politicians but also our competitors around the world have an interest in the attacks on Switzerland," he said.

The remarks are the most outspoken that Ermotti has made since taking up the job of UBS chief executive last November. UBS, which has seen its fortunes recover in recent quarters, had been embroiled in a high-profile tax case in the US, settling with the authorities there over criminal and civil charges of helping US citizens evade tax. As part of those settlements in 2009, UBS agreed to pass over some client details to US authorities, a move seen as a partial breach of Switzerland’s centuries-old bank secrecy traditions.

Since the settlement of these cases, Swiss private banks have ceased to provide offshore bank services to US clients; countries such as Germany and the UK have signed bilateral offshore disclosure agreements with Switzerland. The changes have led some commentators – most recently analysts at Mediobanca – to predict that billions of dollars in offshore money will migrate from Switzerland to other jurisdictions. The stakes for Swiss banking are considerable as this sector accounts for about 12 per cent of Swiss GDP.

In the interview, Ermotti said attacks on Swiss bank secrecy - which has helped the country build up a $2 trillion offshore financial sector - had political as well as economic motives.

He said that an investigation launched recently in France into allegations that the bank helped French clients dodge taxes was being misused in the presidential election campaign. "Politicians want to cash in the taxes. But it's about more than that: Switzerland is a very successful island   internationally with low interest rates, low taxes and attractive banks. Many people abroad don't like that," he said.

One of the most dramatic examples of how pressure on Switzerland has forced change was the purchase in January of Switzerland’s oldest bank, Wegelin and Co. It ceased to be an independent entity and was sold to Raiffeisen.