Asian currencies fell on Wednesday, some of them reversing early gains, undermined by rising global oil prices and concerns over Iran's nuclear ambitions.
Those worries pulled the Malaysian ringgit off an eight-year high and caused the Thai baht and South Korean won to decline half a percent each.
Oil prices climbed to more than $69 a barrel, pressured by concerns US fuel demand will rise and over uncertainty of supplies from Iran, Nigeria and Iraq.
On Tuesday, Iran said it had begun uranium enrichment, which it will build to industrial scale for power generation. The United States believes Iran wants to build a bomb.
"It's risk reduction triggered by Iran nuclear worries and oil prices reaching the highs seen last August, not helped by all the recent banter about the risk to emerging markets from the withdrawal of global liquidity," said Philip Wee, DBS Bank's currency strategist.
Former Federal Reserve Chairman Alan Greenspan warned on Wednesday a global glut in liquidity would result in a fall in asset prices. Greenspan, speaking to a financial conference in Seoul via satellite, said asset prices will begin to fall, but did not predict when that would happen.
Mirza Baig, Deutsche Bank's currency strategist, said the decline in Asian currencies was due to a sharp downturn in global growth sentiment, spurred by the rising energy prices.
Local factors had exacerbated the move, he said, citing some dividend payment outflows from Korea and the ending of foreign currency inflows from BNP Paribas's acquisition of a stake in Shinhan Financial Group, the latter estimated to be worth more than $950 million.
The ringgit hit 3.6645 per dollar, its highest level since Malaysia dropped the currency's dollar peg last July and allowed a faster pace of appreciation. It later fell to around 3.6725.
The baht was quoted as high as 37.93 per dollar, close to Tuesday's six-year high of 37.90. It fell to the weaker side of 38, its decline triggered in part by Bank of Thailand Governor Pridiyathorn Devakula's comments about it being too strong.
The Singapore dollar meanwhile was little changed at about 1.6135 per US dollar, having recovered from a sell-off on Tuesday.
The currency came under pressure after the Monetary Authority of Singapore decided to stick to its two-year-old policy of allowing a gradual, modest rise in the trade-weighted Singapore dollar.