"The euro will probably break up in the next 15 to 20 years," Rogers said in an interview. "Don't get me wrong, I own the euro."

"We've had currency unions in history, they didn't survive, this one won't survive either," he explained.

The euro has been under pressure because of Greece's sovereign debt concerns. But European Union finance ministers agreed to bail out Greece if it will need aid because of its growing public debt, which is forecast to exceed 120 percent of gross domestic product this year.

"If (the euro zone helps) the Greeks, that weakens the fundamentals of the euro," Rogers warned. "As the next government comes to demand concessions, they weaken the currency from within."

"I would let Greece go bankrupt because then everybody will say the euro is a serious currency," he told "Worldwide Exchange."

The UK pound's problems will be caused by Britain's "gigantic debt and huge trade deficit," he said, adding that he doesn't own sterling.

The country's two fortunes – North Sea oil and London's place as a financial hub – are dwindling and there is nothing on the horizon to replace them.

"Most Western currencies, most currencies everywhere are very suspect," Rogers told "Worldwide Exchange."