OMAHA, Neb. (AP) — Billionaire Warren Buffett says the U.S. economy appears weaker than he thought it would be as recently as last fall, but that doesn't change his optimistic long-term view of the country's prospects.

Buffett appeared on CNBC Monday after releasing his annual letter to Berkshire Hathaway shareholders over the weekend.

Buffett says the collapse in oil prices will be good overall for the American economy because consumers will have more money to spend.

But he says the negative effects of falling crude prices hit the oil industry immediately in terms of lost jobs and reduced company values. Buffett says the benefit to Americans trickles in slowly every time they fill up their gas tanks.

Buffett's letter, which reviews the operations of the conglomerate over the previous year, is one of the most widely read business reports.