Russia's economy is in free fall — the government projects a recession of possibly 4.7 percent next year — and President Vladimir Putin deserves much of the blame, says Nobel laureate economist Paul Krugman.

Putin and "his swaggering strongman act helped set the stage for the disaster," Krugman writes in The New York Times.

"A more open, accountable regime would have been less corrupt, would probably have run up less debt and would have been better-placed to ride out falling oil prices. Macho posturing, it turns out, makes for bad economies."

The Russian economy under Putin amounts to a kleptocracy for the benefit of his cronies, Krugman explains. "It all looked sustainable as long as oil prices stayed high." But now oil prices have sunk to five-year lows.

"And the very corruption that sustained the Putin regime has left Russia in dire straits," he writes.

So what's the end game? "Russia will try to muddle through on its own, among other things with rules to prevent capital from fleeing the country," Krugman predicts.

Mohamed El-Erian, chief economic adviser to Allianz, agrees that Putin must change his tune to avoid a disaster.

"The only way for Russia to put in place an economic and financial floor and embark on a sustainable recovery is . . . to start a meaningful re-engagement with the West," he writes in the Financial Times.

If Putin fails to do that, "he will be economically signing Russia up to a higher probability of an economic depression and hyperinflation," El-Erian says.

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