Distressed debt constitutes the juiciest investment vehicle in the United States at this point, says real-estate mogul Sam Zell.

“Our emphasis in the U.S. is buying distressed debt,” he told CNBC. “At the moment, that represents perhaps the best value out there.”

Junk bonds have returned about 5 percent so far this year, compared to a 5 percent drop for the Dow Jones Industrial Average.

Stock opportunities are better overseas than in the U.S., Zell says. “We’re trying to take advantage of places in the world where we see demand creating an environment to succeed,” he said.

Outside of Europe, most major countries have seen their stocks outperform those in the U.S. so far this year.

The best bargains in the United States came in March 2009, when stocks hit 12-year lows, Zell maintains.

“We’ve certainly recovered from that.” The Standard & Poor’s 500 Index has soared 57 percent from its low.

“With a clearer picture of tomorrow, the stock market is cheap,” Zell said. But he doesn’t think that’s where we stand.

“With an uncertain view of tomorrow, the stock market is a problem.”

Zell isn’t the only one bullish on distressed debt.

Junk bonds experienced a $1.1 billion inflow of cash in the week ended June 23, their biggest take since early March, according to EPFR Global.