The euro retreated from a three-year high on Tuesday as investors sold the currency on doubts that the European Central Bank would back away from its pledge to keep buying bonds at next week's meeting.
Digital currencies tumbled, with bitcoin losing as much as 18 percent to a four-week low near $11,000 after reports suggested it was still possible that South Korea could ban trading them, which intensified fears of a wider regulatory crackdown.
Sources close to the ECB told Reuters that the central bank was unlikely to tweak its policy message so soon, as rate setters need more time to assess the outlook for the economy and the euro.
"For ECB policy-makers, they are thinking 'We have to be careful to not feed into this run'," Dragah Maher, U.S. head of FX strategy at HSBC Securities in New York, said.
After its best three-day performance in nearly two years, the euro fell as low as $1.2208 on the Reuters report.
It was already pressured by anxiety over whether German Chancellor Angela Merkel would manage to form a "grand coalition" to govern. Members of the centre-left Social Democrats (SPD) in one of Germany's regions voted against talks with Merkel's conservative Christian Democrats (CDU) on Monday, and fresh headlines on that development triggered a fall in the euro in early European trading on Tuesday.