WASHINGTON (AP) — Alaska Gov. Sarah Palin, touted by GOP presidential candidate John McCain as his expert on energy, seemed to have problems Thursday explaining whether the government bans oil exports — especially from her state's North Slope fields.

A questioner at a town hall-style meeting in Wisconsin said he had heard that at least 75 percent of the oil drilled in Alaska was being sold to China and said, if true, he would like to know why.

"No. It's not 75 percent of our oil being exported," Palin said, suggesting some of Alaska's oil, in fact, may be going abroad but not that much.

"In fact," she added, "Congress is pretty strict on, um, export bans of oil and gas especially."

No Alaska oil has been exported since 2004, and little if any since 2000, according to the Energy Information Administration and the Congressional Research Service.

And Congress has never imposed outright bans on oil exports. Congress prohibited exports of Alaska oil in 1973 when the Alaska oil pipeline was built. But that ban was lifted in 1996 when there were large volumes of Alaska oil coming down from the North Slope and U.S. demand was soft.

The Alaska ban has never been reinstated.

"It's been discussed recently as part of talk about drilling on the Outer Continental Shelf," said Bill Wicker, a spokesman for the Senate Energy and Natural Resources Committee. But he said there's been no active legislation that would reinstate the Alaska ban or any thought on Capitol Hill of banning other U.S. oil or natural gas exports.

Natural gas exports must be approved by the Energy Department under a 1938 law, although such authorization for gas shipments to Mexico, Canada and Japan have been granted for many years. The Energy Department recently indicated it is ready to renew authorization for shipping Alaska liquefied natural gas, or LNG, to Japan.

There are no such restrictions when it comes to oil.

Between 1996 and 2004, about 95 million barrels of North Slope oil, roughly 2.7 percent of Alaska's production, was exported to South Korea, Japan, China and Taiwan, according to the Energy Information Administration.

There have been little or no oil exports since 2000, according to the Congressional Research Service. The EIA said there have been no Alaska oil exports since 2004.

The United States exports a relatively small amount of oil and petroleum production as Palin acknowledged as part of her answer, which largely focused on the need for more domestic drilling.

"It's not a huge portion of any domestic supply being exported," Palin said toward the end of her response, and seemed to contradict her earlier view that Congress bans exports.

Last year, the United States exported 523 million barrels of petroleum products, of which only a small amount was crude oil. That year it imported more than 4.7 billion barrels of oil and oil products.

The United States exported 822 billion cubic feet of natural gas, almost all by pipeline to Canada and Mexico, and a small amount of liquefied natural gas, or LNG, to Japan and Mexico in 2007, according to the EIA.