ALBANY — Gov. Andrew M. Cuomo, pushing New York to become the first state to enact major new gun laws in the wake of the massacre in Newtown, Conn., plans on Wednesday to propose one of the country’s most restrictive bans on assault weapons.

New York is one of seven states that already ban at least some assault weapons. But Mr. Cuomo has described the existing law as having “more holes than Swiss cheese,” and he wants to broaden the number of guns and magazines covered by the law while also making it harder for gun makers to tweak their products to get around the ban.

Mr. Cuomo, a Democrat, will outline his proposal in his State of the State address, but even before he speaks, he has incited anxiety among gun owners by acknowledging in a radio interview that “confiscation could be an option” for assault weapons owned by New Yorkers. Since that interview, Mr. Cuomo has not mentioned the idea, and his aides have acknowledged that it would be impractical.

But gun rights groups have seized on the comment, even promoting a petition on the Web site of the White House that declares, “We do not live in Nazi Germany,” and asks the Obama administration to block any effort at confiscation by Mr. Cuomo.