Africa May Become ‘Most Productive’: Economist

The dynamics of the global economy are changing rapidly, and Africa may become the most productive continent one day, said Jacob Frenkel, chairman of JPMorgan Chase International and former governor of the Israel's central bank.

In an interview Monday on CNBC's "Squawk on the Street," Frenkel also warned that central banks cannot sustain monetary easing policies in the long term.

"The center of gravity of the world is changing very rapidly," Frenkel told CNBC. "It is related to those countries that are growing and getting younger. They will be the destination for the future."

"Africa, for example, if they get their act together, they may become the most productive future continent. In terms of size, their population is very young and growing," he said.

On the other hand, he sees problems for Japan with its aging population, with the only growing segment of the country's population being those over age 80. "It will have significant budgetary consequences," he said.

"In the U.S., the propulsion of the population above 65 will be rising and growing, leaving very little room for the government to do the right thing," he added.

On the Federal Reserve's quantitative easing, "given the circumstances it seems to be the right policy but we need to realize that this is not sustainable in the long run," Frenkel said. "A lot of elements in unemployment is structural, and it is not just the business cycle. There are a lot of structural elements in the employment rate which means we may see a period with negative real interest rates for a long time."

"We have had a situation of overburdening monetary policy," he said. "That is not healthy. It is a good strategy to give time to the governments to do their job, but you cannot give too much time."

— By CNBC's Paul Toscano. Follow him on Twitter and get the latest stories from "Squawk on the Street" @ToscanoPaul