Options trading suggests the euro is nearing the end of its advance against the dollar and there is "no hint of a crisis" in the world's main reserve currency, according to RBS.

"There are surprisingly few signs of real fears of an outsized euro-dollar move to the upside," Alan Ruskin, head of international currency strategy in North America said.

"The market appears to be taking an appropriate view that we are sucking the last juice out of the short US dollar trade that probably has a maximum of 10 big figures left in it to $1.60 versus the euro."

Measures of short-term volatility, volatility curves and risk reversals not only suggest that there is no US dollar crisis looming, "on the contrary, at least when it comes to the bellwether euro-dollar currency pair, they are signalling quite the opposite," Ruskin wrote.

The euro has appreciated 7.1% this year and climbed above $1.50 two days ago for the first time since August 2008. It was little changed on Friday at $1.5001.

The euro touched $1.6038 on 15 July 2008, the strongest level for the 16-nation currency since its debut in 1999.