Treasury Secretary Timothy Geithner said on Wednesday that fallout from the European debt crisis along with fears of Iran and higher oil prices posed the biggest threats to the U.S. economy.

Europe is still facing a very difficult, very challenging period. They are likely to have weak growth, Geithner said in an interview with Fox Business TV.

You have, obviously, the fear of Iran and oil prices, even though that is not hurting the economy today, people can still feel that in their pocketbook today, he said.

(Reporting by Glenn Somerville, Rachelle Younglai)