But analysts dismissed the market reaction as knee-jerk. With sentiment for the dollar remaining strong and more people betting against Asian currencies due to political and economic uncertainty, they could soon head towards levels that would prompt the authorities to react. "They might not need to be in the market at this point. But I would not rule out the possibility," said Ms Chia Woon-Khien, chief analyst at SEB Merchant Banking in Singapore.

"Normally, there are three conditions that prompt central banks to act - when currencies drop below certain target levels, when the pace is out of synch with others in the region, and when domestic factors lead to speculative actions. These risks are still very prominent," she said.

Taiwan's central bank, frequently in the market for smoothing operations, has been particularly vigilant in the past few weeks to support the currency which is hurt by outflows and poor sentiment brought about by uncertainty over the tech sector. Last Monday alone, dealers estimated its intervention accounted for a third of the day's $689 million turnover.

Forex dealers in the Philippines said the central bank might have spent around $250 million to $300 million during the first half of this month to defend the peso. The bank says it has not been in the market since last week, but adds it does not rule out the possibility in the future. In Thailand, government officials have sent mixed signals to the market recently on currency intervention. While one minister said the authorities might resort to short-term market intervention if excessive volatility in the baht hurt the economy, another senior minister said there was no need to prop it up.

(Reuters)