"A puzzling feature of recent exchange rate developments is that foreign exchange markets greeted the arrival of new positive information about the United States economy with a strengthening of the US currency.

At the same time, positive news about the euro economy failed to have a comparable impact on the euro," Welteke wrote in an article in the Financial Times.

"This may be a situation in which analysts and traders are exhibiting herd-like behaviour with respect to the acquisition of information.

"It seems that they do not focus on those variables that they would, acting in isolation, believe to be most relevant for the valuation of a currency. Rather, they concentrate on variables which they believe other analysts will focus on."

Welteke expressed confidence that the "powerful correcting forces unleashed by unexploited profit opportunities" would in due course sort the situation out.

Given efficient financial markets, exchange rates would eventually come into line with fundamentals, Welteke said.

"Monetary policy contributes to this process in important ways by minimisingpolicy-induced uncertainties and by remaining focused on ensuring the currency's internal stability," Welteke said.