President Bush is spending Saturday promoting alternative fuels, after oil and gasoline prices reached record highs on Friday.
Mr. Bush is touring the California Fuel Cell Partnership in West Sacramento, California, where researchers are working on hydrogen fuel cells for cars. He said in his weekly radio address that the technology could help wean Americans away from what he called "gas-guzzling vehicles."
In the Democrats' radio address, Senator Bill Nelson said flatly that an oil crisis is on the way, whether it is caused by a terrorist attack in the Persian Gulf, U.S. tensions with oil-producer Venezuela, or hurricane damage to U.S. oil refineries.
Crude oil prices topped $75 a barrel on Friday, over concerns that the oil supply could be interrupted while U.S. gasoline reserves are shrinking.
The heads of some of the world's biggest oil companies are meeting with a number of national energy ministers in Qatar today to discuss the situation.
Oil producer Iran is embroiled in an international disagreement over its nuclear weapons program. Nigeria is battling unrest in its oil-producing delta region. And although the United States buys Venezuelan oil, the president of Venezuela, Hugo Chavez, is a fierce critic of the Bush administration.
Some information for this report was provided by AP and Reuters.