Billionaire Warren Buffett says he doesn't think another U.S. banking crisis is likely, but sovereign debt issues in Europe remain a concern.

Berkshire Hathaway's CEO and Vice Chairman Charlie Munger held a news conference Sunday one day after spending the day answering their shareholders' questions.

Buffett says European banks could have problems if those nations are unable to resolve their debt problems.

Buffett says it's hard to say whether the countries in the European Union will be willing to stay tied to a single currency if they have to keep bailing out other nations.

Buffett says he thinks Europe may need to find a way to have a more unified fiscal policy among the different countries.