Tourism accounts for 5 percent of Swiss GDP and has been one of the industries worst affected by the strong franc, which hit a series of record highs against the dollar and the euro in 2011.

"The rate between the Swiss franc and euro has led to losses, especially to a loss of European tourists, from Germany in particular," Jean-Francois Roth, president of Swiss Tourism, told a news conference in Lausanne.

"This is a capital element for us. The strength of the Swiss franc weighs on our capacity to compete with other tourism destinations," Roth told Reuters.

The SNB capped the Swiss franc, which almost reached parity versus the euro last summer, at 1.20 francs per euro to prevent the economy from tipping into recession. The strong franc has been a burden to Swiss exporters as well as sectors like tourism, and many have said the measure does not go far enough and that the franc is still overvalued.

"There is little perspective of seeing the cap raised in coming weeks," Roth said.

Neighbouring Austria, France, Italy and Germany are rival destinations for people booking holidays in the Alps.

Tourists spent 33.1 million nights in Switzerland between January and November last year, a drop of 2 percent from the previous year, according to the latest figures from the Swiss statistics office, released last week. Foreigners accounted for 18.5 million nights during the period, a drop of 3.3 percent.

For the month of November, nights spent by European tourists (excluding Swiss), dropped by 4.4 percent. German tourists fell by 11 percent, while those from the Netherlands dropped by 11 percent against the same month last year, while U.S. tourists spent 3.6 percent fewer nights in Switzerland.

The SNB will continue to enforce its franc cap versus the euro with the utmost determination and remains prepared to buy foreign currency in unlimited quantities, one of the central bank's governing board members Jean-Pierre Danthine said in Zurich on Tuesday.

(Reporting by Stephanie Nebehay; editing by Stephen Nisbet)

• A Permanent Economic Emergency