Asian shares, oil and copper extended losses on Thursday after data indicated little respite for Chinese manufacturers, keeping the outlook unclear whether policymakers in the world's second-largest economy will feel compelled to follow the global rush of stimulus action.
Safe-haven assets, including the dollar index gained.
The franc, which the Swiss National Bank capped at 1.20 per euro a year ago to stave off a recession, has been on a weakening trend against the common currency for the past fortnight.
The European Central Bank's bond buying plan has led investors to breathe a sign of relief that the worst of the 3-year old debt crisis may be over, causing a jump in risk appetite, yet that may now be fading.
"European challenges are leading markets to question the recent euro strength," analysts at Barclays said.
The Swissie touched an eight-month low of 1.21831 per euro on trading platform EBS on Monday but has since clawed back some turf. Currency strategist at UBS expect range-trading in euro/Swiss, with support at 1.2035 and resistance is at 1.2200.
PMI manufacturing data for European countries is due later in the session.
"In Europe, eurozone flash PMIs will provide the first indication of whether the pick-up of sentiment in financial markets has fed through to the real economy," analysts at BNP Paribas said. "We expect moderate increases in both the manufacturing and services surveys, but for these to remain in sub-50, recessionary, territory."
Investors were also cautious before Spain goes to the market to raise funds as it mulls if and when to seek a bailout that would open the way for European Central Bank intervention.
The pressure is ramping up on the euro zone's fourth largest economy to seek financial help. But Spain remains reluctant to ask for aid which may cause it to lose some fiscal sovereignty and potentially place its economy under further growth-stifling austerity.
The franc fell 0.4 percent against the dollar to trade at 0.9306 by 0643 GMT compared to the New York close.
The franc was little changed against the euro to trade at 1.2088.