But he declined to comment directly on the European single currency's recent slide to record lows against the greenback.

"The buck stops here in the United States," he told a newsbriefing at the World Economic Forum's annual meeting.

"As long as we manage the fundamentals of our economy well, and we maintain what I think is a sound policy of recognizing that a strong dollar is in the national interest, I don't think we have anything to fear from successful currency arrangements in other countries," he said.

Europe's fledgling single currency went into a virtual free-fall last week, plummeting below parity with the dollar and raising speculation whether the European Central Bank may raise official interest rates next week to help prop it up.

Summers has made it his routine never to comment directly on currency movements, and has consistently stuck to the line that a strong dollar is good for the US economy because it helps to keep inflation and interest rates down.

"I don't have anything to add...to the things I've said inthe past on our dollar policy," he said.

Summers refused to be drawn on whether the booming US economy, which expanded at a rate of 5.8 percent in the fourth quarter of last year, was in danger of overheating and thus posed a threat to the rest of the world.

"The momentum of the US expanison should continue, albeit with fluctuations from quarter to quarter," he said. "The fundamentals of our economy are sound." As the US economy is about to enter a record 107th month of uninterrupted expansion in February, concern has mounted that strong growth and tight labor markets will force the Federal Reserve to raise interest rates sharply to prevent the economy from speeding out of control.

The Fed is widely expected to bump up the key overnight fed funds bank lending rate by a quarter percentage point to 5.75 per cent when its policymakers next meet Feb. 1-2.