LONDON: The euro hit a 4-1/2-month high on Monday as optimism over US-China trade relations and the global growth outlook knocked demand for dollars.
Thin end-of-year volumes exacerbated the broad weakness in the US currency, which dipped for three straight sessions and on Friday suffered its biggest one-day fall since June.
Improving investor sentiment, which has discouraged buying of the dollar as a safe haven, was further boosted when China's central bank unveiled a measure to help lower borrowing costs and boost economic growth. Investors also cheered a report forecasting an 8% rise in China's 2019 retail sales.
The euro climbed as high as $1.1211, its strongest level since Aug. 13, before settling at $1.1192, up 0.2% on the day.
Signs that the euro zone economy has turned a corner have lifted the EU single currency in recent weeks.
The dollar index, which measures the currency against a basket of rivals, weakened 0.1% to 96.826.
With Friday's loss, the index's gains for the year have shrunk to around 0.7% -- the weakest annual rise for the dollar since 2013.
"The main drivers of the weaker dollar have likely been risk appetite holding up in the wake of comments from the US pertaining to a Phase 1 trade deal recently, as well as the US Federal Reserve's continued repo operations, which have recently been undersubscribed," MUFG analysts said.
The greenback lost 0.3% versus the Japanese yen, to 109.17 yen.
Sterling climbed to as high as $1.3134, 0.4% higher.
Against the euro, the pound recovered earlier losses and was last up 0.2% at 85.24 pence. Concerns that Britain is headed for a disruptive "hard Brexit" at the end of 2020 had been hurting the pound since mid-December.
China's yuan strengthened to touch 6.9752 in the offshore market, its highest since Dec. 13.
The Australian dollar, which is sensitive to global sentiment, rose 0.2% to hit another five-month high of $0.6999 . The New Zealand dollar did the same with a 0.3% gain to $0.6725.
Marshall Gittler, chief strategist at ACLS Global, said it was noticeable how little currencies had moved during 2019, with very low volatility and narrow trading ranges, which he put down to "economic and monetary policy convergence".
"I expect less of both in 2020, for two reasons," he said, noting the expected end of the Sino-US trade war, which should lead to broader economic recovery across the world.
The second reason, Gittler said, was that inflation seemed to have bottomed out and "conceivably some countries could start thinking about hiking rates, which would encourage monetary policy divergence".
Later on Monday, investors will stay tuned for the Chicago Purchasing Management Index for clues about the health of the US economy.