Donald Trump's prediction that the U.S. economy was on the verge of a "very massive recession" hit a wall of skepticism on Sunday from economists who questioned the Republican presidential front-runner's calculations.

In a wide-ranging interview with the Washington Post published on Saturday, the billionaire businessman said a combination of high unemployment and an overvalued stock market had set the stage for another economic slump. He put real unemployment above 20 percent.

"We're not heading for a recession, massive or minor, and the unemployment rate is not 20 percent," said Harm Bandholz, chief U.S. economist at UniCredit Research in New York.