"We've really been at the upper range of the euro for some time," he told CNBC. "But over the past few years, we've had quite aggressive selloffs, and I would suggest that we're at risk of a similar selloff." Riddell thinks the euro could hit the lows of late 2008 or even 2010, around 1.1875.
The euro isn't just facing headwinds against the dollar, he adds. "We're breaking to some key areas in euro-Aussie," he says, adding that there is a risk that cross could fall to 1.20.
"We're getting a lot of technical pressure on the euro."
You can watch the discussion, and see the disturbing charts, on the videotape.
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