The dollar slipped against the safe-haven Japanese yen on Friday, after a U.S. launch of cruise missiles at an airbase in Syria, Reuters reported.
An U.S. official said the strike has already been completed.
The dollar erased its early modest gains and slipped 0.3 percent to 110.46 yen JPY=, compared with a session high of 110.99.
U.S. President Donald Trump said on Thursday that "something should happen" with Syrian President Bashar al-Assad after a deadly poison gas attack in that country.