Tokyo - The euro briefly fell to a 20-month low against the dollar early Monday after Italian Prime Minister Matteo Renzi announced his resignation after losing a referendum on constitutional reform.
The euro hit $1.0508 at 23:22 GMT, the lowest since March 2015 and down from $1.0664 late on Friday.
The single currency has since rebounded to $1.0554.
Interior Ministry projections suggested the No camp, led by the populist Five Star Movement, had been backed by 59.5% of those who voted.
The defeat and Renzi's departure will plunge Italy into a new phase of political uncertainty and possible economic turmoil.
President Sergio Mattarella will be charged with brokering the appointment of a new government to run Italy until the next general election, which is due to take place by the spring of 2018.