The yen strengthened the most in two weeks against the dollar as oil prices slumped to a five-year low, feeding demand for haven assets.

The yen appreciated 1 percent to 119.48 per dollar as of 5 p.m. New York time after adding as much as 1.5 percent, the biggest gain since Dec. 16. It advanced 1 percent to 145.25 versus the euro. The 18-nation common currency traded at $1.2156 after falling to $1.2124, the weakest since July 2012. The Aussie slid as much as 0.2 percent to NZ$1.0422.

The Bloomberg Dollar Spot Index, which tracks the U.S. currency against 10 trading partners, dropped 0.4 percent to 1,128.69. It closed at 1,133.13 on Dec. 23, the highest since March 2009, and is up 11 percent this year.

West Texas Intermediate crude for February delivery slid as much as 91 cents to $52.70 a barrel in New York, the lowest since May 2009, before trading at $53.89.

Source : Bloomberg