The Bush administration is considering a proposal to require that gun buyers register semiautomatic assault rifles of the kind linked to mounting drug-related violence.

An administration official acknowledged that the proposal, among others, is being studied by government agencies as the administration weighs additional steps to control the deadly weapons."I've been asked to give comments on that and a lot of other proposals that were made," Stephen Higgins, director of the Bureau of Alcohol, Tobacco and Firearms, said Wednesday. "The administration is involved in looking at the entire issue getting input from a lot of people, of which this agency is one."

Higgins made the comments as he discussed the administration's move to widen its temporary import ban on assault rifles to include virtually all foreign-made models.

Earlier Wednesday, the White House had announced that 24 models of semiautomatic assault rifles were being added to the list of weapons already covered by the 90-day ban on imports imposed last month.

The initial import suspension covered as many as 400,000 weapons. The additional list covers permits to import up to 250,000 more, Higgins said.

"We think we've got 99.9 percent" of the foreign-made semiautomatic rifles, Higgins said.

The 90-day period will enable ATF to determine if any of the weapons on the list are used for legitimate sporting purposes. The Gun Control Act of 1968 bans the importation of weapons that are not used for legitimate sporting purposes.

"These are weapons which are identical in design" to those on the original list, Higgins said. "They are basically paramilitary in appearance, they are large-capacity magazines."

Importers have been given 30 days to "substantiate that the weapons they are selling are being used for sporting purposes," he said.

At the White House, presidential spokesman Marlin Fitzwater said a prime reason for expanding the ban was to prevent a few gun manufacturers from gaining an unfair competitive edge.

But he conceded that "there is some unfairness" because the ban still does not affect American-made high-powered rifles, which account for 75 percent to 80 percent of the market.

"Unfortunately, it is not something we can do anything about," Fitzwater said. "To do anything about domestically manufactured weapons would require a change in the law."