The euro held near a six-week high against the dollar on Tuesday, threatening a break past $1.37 that could quickly see it back at levels expected to provoke at least a verbal response from the European Central Bank.
Dealers said there was strong support for the euro around its 55-day moving average at $1.3698 and it retreated after touching that level overnight.
A number of analysts from the global financial system's biggest banks have returned to arguing in recent weeks that the dollar is on the verge of a push higher, given the prospect of rises in U.S. interest rates sometime next year.
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But the greenback disappointed heavily on similar bets at the start of this year and there is little sign yet of a move higher. The eurohas recovered all of the ground lost since the ECB announced a new round of monetary easing a month ago.