Delivering remarks at a luncheon organized by the International Economic Forum of the Americas, Former Fed Chairman Paul Volcker said he believed that the United States was undergoing a difficult but necessary political and economic shakeup.

Referring to comments made earlier by Canadian Finance Minister Jim Flaherty painting an optimistic picture of the Canadian economy, Volcker said that the same could not be said for the United States.

The U.S. economy is undergoing a "prolonged period of adjustment", Volcker said, adding that this was not a nine to 12 month adjustment process. The financial crisis is very serious, and hopefully the current difficult situation will be a healthy adjustment, he said.

By Erik Kevin Franco and edited by Nancy Girgis