Sen. Dianne Feinstein on Tuesday rejected a plan by the Alcohol, Tobacco, Firearms and Explosives Bureau to review the sale of bump stocks and other devices that can accelerate the firing power of semi-automatic weapons, arguing the ATF is not authorized to regulate them and instead Congress must act.

“The ATF lacks authority under the law to ban bump-fire stocks, period,” the California Democrat said in a statement. “The agency made this crystal clear in 2010 and again in a 2013 letter to Congress, writing that ‘stocks of this type are not subject to the provisions of federal firearms statutes.'”