* Moderately optimistic on economy but lots of uncertainty
* Will resolutely prevent excessive rise in franc
* Residual deflation risks continue
(Adds more comments on monetary policy, regulation, currency)
By Sam Cage
ZURICH, Jan 22 (Reuters) - Raising interest rates would be inappropriate for the moment and the Swiss National Bank will continue to prevent any excessive rise in the Swiss franc, the head of the central bank was quoted as saying on Friday.
The SNB has a moderately optimistic outlook for the Swiss economy but plenty of uncertainties remain, meaning it would be premature to start tightening monetary policy at the moment, the Wall Street Journal quoted SNB Chairman Philipp Hildebrand on Friday as saying.
"What we do know is that at the moment certainly raising interest rates would be inappropriate," Hildebrand said. "Our policy is clear: we will resolutely prevent an excessive appreciation as long as there are deflationary risks."
Switzerland emerged from recession in the third quarter of last year, and the SNB forecasts growth of 0.5 to 1.0 percent for 2010 and inflation of 0.5 percent.
Keeping the franc from appreciating against the euro is one way the central bank can stave off deflationary pressures.
The SNB relaxed its intervention policy, launched in March 2009 to prevent a rise in the franc as part of a package of drastic measures to fight a deep recession and deflation risks, at its Dec. 10 meeting.
The franc fell after Hildebrand's comments and was down 0.2 percent against the euro compared with Thursday's New York close at 1.4709 per euro. EURCHF=
"We continue to have considerable residual deflation risks, particularly in the event that we were to be hit by a renewed shock of some sort, and clearly the exchange rate shock would be one that would be particularly damaging regarding deflation risks," Hildebrand said.
"We are equally committed to preventing deflation as we are to preventing inflation," he said. "We have used the interest rate mechanism all the way. We are obviously at a zero rate policy." (Editing by Andy Bruce)