"An investment manager at Supervised Investments, Phil Carden, said the move to create money "out of thin air" was "hugely inflationary".
"It's a direct and blatant attempt to ignite inflation because they're scared of deflation," he said.
He said it was the lesser of two evils, as deflation was a bigger menace to the US than inflation. If asset prices started to fall across the economy, it would threaten the country's ability to pay back $US11 trillion in national debt, he said."