Desperate times and desperate economic news require desperate policy actions, says Nouriel Roubini.

"It is hard to get any worse than this, but the next few months will serve up macro news that is even worse," the economist wrote in Forbes magazine.

Roubini expects the news will push the Fed into more "crazy" policies.

The Fed, Roubini says, is now relying on "massive quantitative easing and direct purchases of private sector short-term and long-term debt" to push down short-term and long-term market rates.

It's a policy Roubini believes will lead to much higher interest rates on public debt, weaken the dollar, and increase concern among foreign investors.

"Most of the new bailout actions and new programs will be financed via injections of liquidity rather than an issuance of public debt," Roubini says.

"And now Bernanke is suggesting that the Fed start purchases of long-term government bonds as a way to reduce long-term market rates."

Stag-deflation, Roubini's term for combined recession, deflation, and economic stagnation, has already forced the Fed to flood financial markets with over $2 trillion and slash its funds rate.

However, Atlanta Fed President Dennis Lockhart believes the U.S. central bank can continue to boost market liquidity even though interest rates cannot fall below zero.

"There are many other mechanisms the (FOMC) can use to provide liquidity," Lockhart said during a recent energy conference.

On Monday, another top Fed official said bank has other tools it can employ and that fiscal policy could start to play a bigger role in spurring the recession-mired economy.

"Given that interest rates cannot be negative, further monetary-policy actions are limited by the zero lower bound for interest rates," Boston Federal Reserve President Eric Rosengren said in remarks prepared for delivery to a conference in Geneva, Switzerland.

"While other monetary policy tools can be employed, increasingly many observers and commentators are suggesting that fiscal stimulus will be an important element of economic recovery," he said.