The U.S. is headed for a recession in the next two years as excessive fiscal stimulus from the President Donald Trump administration takes the economy into unsustainable territory, Adam Posen, president of the Peterson Institute for International Economics, told CNBC Tuesday. Posen, who served at the Federal Reserve Bank of New York in the mid-90s, said that GDP (gross domestic product) growth targets of 3 percent or more are unobtainable given current productivity and employment rates in the U.S. Add to that intended tax cuts and financial deregulation under Trump and the country will find itself trapped in a boom-bust cycle, Posen said. "The work force is only growing at 0.5 percent and productivity's at 1 percent so it can't reach these 3-4 percent growth targets. If unemployment is, unfortunately, about as low as it's going to go, you can't pick this up," he told CNBC Tuesday.

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"Then you're going to get financial deregulation, which in some ways is a good thing but is likely to feed further credit boom, as it's always done in the past, so the Fed will start tightening against this – that's your boom-bust cycle." Already the Federal Reserve is trying to manage signs of a growing U.S. economy by gradually increasing interest rates. Earlier this month, it hiked rates by 25 basis points, its first such move this year and only the third since the financial crisis. However, further increases are expected this year, with Posen anticipating three extra hikes by December and more still in 2018. "The Fed is going back to normal in the sense that it's not scared to do the moves that it would normally do in response to the forecast," he said.