(Reuters) - The dollar hit a record low versus the Swiss franc and a four-month trough against the yen on Monday as the impasse over raising the U.S. debt ceiling unsettled financial markets and fueled demand for perceived safe-haven currencies.

The Swiss franc was the biggest beneficiary of the demand for safe havens, pushing the dollar nearly 2 percent lower to an all-time low of 0.8021 franc on trading platform EBS. The euro fell the same amount versus the Swiss currency.