The Swiss franc traded near flat against the euro on Monday compared with last Friday's close though still weaker than its average level last week ahead of retail sales data later in the session.
The franc traded at 1.5528 to the euro against 1.5533 at the New York close on Friday. At one stage last Friday the franc weakened as far as 1.5565, but over the rest of last week it held mostly between 1.5460 and 1.5525.
"Given rather favourable fundamentals and with EURCHF unable to close (last) week above the critical levels of 1.5543, we expect the cross to continue to trade heavy," UBS Investment Research said in a market comment.
The franc traded at 1.2191 per dollar, slightly weaker than the previous close at 1.2172.
Swiss retail sales data for March is due to be published at 0715 GMT. In February retail sales increased by 0.4 percent compared with a year earlier.
Philipp Hildebrand, member of the governing board of the Swiss National Bank, speaks on the financial markets at 0645 GMT at an event in Zurich.
The SNB has helped stem a franc slide earlier this year by saying at the end of April the currency was too low against the euro at a time when volatility in financial markets already made the safe-haven currency more attractive.
A weak franc would effectively loosen monetary policy by importing inflation and boosting income from exports, thereby stimulating growth - an unwelcome effect in a period of SNB tightening.