BERN (AFX) - Swiss National Bank president Jean-Pierre Roth said the continued weakness of the euro against the Swiss franc compared with pre-Sept 11 levels is only temporary. Speaking to a financial conference in Vienna, Roth said: "The development was due to extraordinary circumstances. Therefore the effect is only temporary." Prior to the strikes, the euro was trading at around 1.53 sfr. It fell briefly to under 1.45 sfr and has since stabilised around 1.45-1.47 sfr. Roth also said: "The value of (Switzerland's) independent monetary policy should not be underestimated." The independence allows Switzerland's monetary policy to be adapted to the needs of the national economy, he noted.