New York City Mayor Michael Bloomberg said he had advised President-elect Barack Obama's transition team to boost U.S. economic growth by fixing the credit markets so that cities and states can resume borrowing to build infrastructure projects.

That would revive the economy much more effectively than the first federal fiscal stimulus plan that the mayor, a self-made billionaire, said only amounted to a "blip" because all it did was spur flat screen TV purchases.

Bloomberg said the U.S. government should "promote" the insurance of capital projects, as long as a city, for example, is rated at least "A" by a credit rating agency. A single "A" rating is five notches below the highest rating of "AAA."