Investors crushed the euro to well below $0.91 yesterday as they scrambled to buy dollars after regaining faith in the future of the slowing US economy.

Traders shrugged off a widely anticipated decision by the European Central Bank to leave key rates unchanged, with the minimum bid rate for its regular refinancing operations still at 4.75 percent.

In late trade, the euro fell to $0.9055 from $0.9180 the previous evening in New York. The single currency's drop was "worrying", said Canadian Imperial Bank of Commerce economist Ms Audrey Childe-Freeman.

Investors had forced the euro into a retreat after its strong gains in past months on the back of fears of a US recession, she said.