Updated

Federal Reserve Chairman Ben Bernanke said he was concerned about the U.S. budget deficit, noting in a letter released Tuesday that the aging of the population will increase the pressure on the budget.

"I am quite concerned about the intermediate to long-term federal budget outlook," Bernanke said in a letter to Sen. Robert Menendez following up on the Fed chief's Feb. 16 testimony to the Senate Banking Committee.

"In particular, the budget is expected to come under severe pressure as impending demographic changes fuel rapid increases in entitlement spending. By holding down the growth of national saving and real capital accumulation, the prospective increase in the budget deficit will place at risk future living standards of our country," Bernanke said.

"As a result, I think it would be very desirable to take concrete steps to lower the prospective path of the deficit," he said in the letter, which was dated March 9.

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