Republican senators are accusing President Obama of pushing a "less-than-honest" claim about the scarcity of domestic oil, after a U.S. Geological Survey study showed the United States might actually hold a quarter of the world's untapped, undiscovered supply.

The president often uses a much different statistic in speeches.

He said Tuesday, as he has before, that "the problem is we use more than 20 percent of the world's oil and we only have 2 percent of the world's proven oil reserves."