The Trump administration took a step toward cooling the gun control debate on Saturday after beginning the regulatory process needed to ban the controversial firearms add-ons known as bump stocks.

Following the shooting at a Florida high school last month in which 17 people were killed, President Donald Trump urged that the Department of Justice work toward a ban on bump stocks.

These devices played a role in another, earlier mass shooting in Las Vegas last October. The gunman’s weapons included bump stocks, attachments that enable semiautomatic weapons to fire at speeds approximating that of fully automatic arms.

Although the Florida shooter did not use these bump stocks, they have remained at the center of the gun control debate since Vegas.

On Saturday the DOJ announced its proposal to classify the equipment as machine guns banned under the federal law, something that the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives found not to be the case in 2010.

ATF’s decision at the time found that bump stocks did not amount to machine guns and could not be regulated unless Congress amended existing firearms law or passed a new one, something that may happen soon.

Saturday’s announcement is likely to result in a major backlash among Republicans, strong Second Amendment advocates and gun manufacturers.

On Friday, Gov. Rick Scott, R-Fla., broke with the National Rifle Association in signing a bill changing the age to buy guns in the state to 21 from 18. The result: an almost immediate legal challenge by the NRA, which announced that it had filed suit against the state, arguing that the age provision violated the constitutional right to bear arms.

The NRA did not immediately respond to The Associated Press’ requests for a comment on the DOJ bump stock proposal.

The proposal still needs the approval of the Office of Management and Budget.

The Associated Press contrived to this report.