Former Federal Reserve Chairman Paul Volcker says Europe’s debt problems have forced its central bank to go beyond its traditional role in order to limit the cascading effect of the crisis.

“(The ECB) is being asked to do things that are out of order in terms of their basic mission, which is to maintain monetary policy in Europe,” Volcker told CNBC.

“Emergency accommodation was not part of their mission. But events have forced that upon them."

Paul Volcker (Getty Images photo)

Volcker says his biggest concern is whether European Union policymakers can convince markets they can hold the bloc together.

“There's some difference of opinion as to how to proceed politically…all that makes it very difficult," says Volcker. "I think they have the elements of a program agreed. But, whether it's agreed in the size and the force that's necessary remains in question.”

“They have to provide some funds to support Italy and Spain during this crucial period. Greece has been relieved of some of its debt burden. (These) are all important steps, but they haven't been implemented in full yet and with sufficient force.”

Volcker describes the U.S. economy as "slogging" along, with unemployment and the housing market remaining key concerns. “People are unhappy and understandably so,” he says.

“The Federal Reserve has interest rates down to zero and ample liquidity in the economy obviously (it) has done what it can do.”

European Central Bank policymaker Juergen Stark says the European sovereign debt crisis can only be solved by euro zone governments getting their budgets under control.

"Permanently continuing the measures of the ECB cannot solve the crisis,” Stark told Reuters.