The Swiss franc is once again under appreciation pressure as scared investors flock to the safe haven currency and ditch the euro. Even German Bunds may now be a risky bet, with Societe Generale warning of contagion risk from the European periphery.

Citi analysts said today that Switzerland's resilient economy is putting appreciation pressure on the Swiss franc, which usually trades at about 1.20 against the euro. It is maintained at roughly this level by a 'currency floor' imposed by the Swiss National Bank, which resolved last September to keep the euro/Swiss franc spot rate above 1.20. It does this by buying unlimited quantities of euros.