OMAHA , Neb. (MarketWatch) -- Warren Buffett said Saturday that he's bearish about the ability of all currencies to hold their value over time because of massive deficits being run up by governments in the wake of the global financial crisis.

The Berkshire Hathaway Inc. BRK.A, +1.30% BRK.B, +1.18% chairman also warned shareholders attending the company's annual meeting that the Greek debt crisis will produce "high drama" and said it's unclear how it ultimately will be resolved.

The financial crisis was stemmed by massive monetary and fiscal intervention in developed economies like the U.S. and the U.K. That's shifted a private-sector debt mountain on to governments, increasing concern about sovereign risks.

One concern is that governments will print lots of new money to pay debts, undermining the value of currencies and triggering a damaging bout of inflation.

"Events in the world over the last few years make me more bearish on all currencies in terms of holding their value over time," Buffett said.

If countries could run deficits of 10% of GDP and do it for a long time "the world would have been doing this for a long time already," Buffett said. "It can't be kept up."

"How the world weans itself off huge deficit financing is going to be difficult to watch," he added.

Still, Buffett noted that as long as the U.S. borrows in U.S. dollars, there's "no possibility of default."

"You don't default when you can print your own currency," he added.

Sovereign debt concerns have hit Greece hardest so far because the country has one of the biggest budget deficits and debt loads of any country in Europe's single-currency zone. The country was also found to have understated its deficit twice, shaking investor confidence.

Greek bond yields have soared and the country's debt rating has been slashed to junk status. This has made it almost impossible for the country to refinance some of its debt mountain at realistic interest rates.

Greece is reportedly promising 23 to 24 billion euros of austerity measures, such as a three-year pay freeze for public-sector workers. In return, European leaders are preparing a bailout that could be as large as 120 billion euros over three years. Earlier in the week, doubts about Germany's commitment to helping Greece triggered a surge in sovereign bond yields that cut all but the most creditworthy countries out of the market.

Buffett said Saturday that Europe's monetary union has created a "really interesting situation."

Greece is a sovereign country in terms of its own budget, "but they can't print their own currency," he noted.

"You may be seeing a test case play out there. A country not using its own currency and yet it is sovereign in terms of making its own promises to its citizens," Buffett explained.

"I don't know how this movie ends," he warned. "I try not to go to movies like that."