President Trump on Wednesday signed legislation aimed at cracking down on illegal fentanyl and toughening prison sentences for those who traffic the drug.

Trump signed the Halt All Lethal Trafficking of Fentanyl Act at a White House ceremony, where he was joined by lawmakers and individuals whose family members have died from fentanyl overdoses.

The president called the bill signing a “historic step toward justice for every family touched by the fentanyl scourge as we sign the HALT Fentanyl Act into law.”

“We’ll be getting the drug dealers, pushers, and peddlers off our street, and we will not rest until we have ended the drug overdose epidemic,” Trump said. “And it’s been getting a little bit better, but it’s horrible.”

The bill, which received bipartisan support in the House and Senate, permanently categorizes all fentanyl-related substances, including copycat synthetic versions of the drug, under Schedule I in the Controlled Substances Act.

That categorization gives law enforcement greater authority to crack down on the spread of the drug and carries stronger penalties for those convicted of possessing or distributing the drug.

The White House has argued that the legislation will discourage cartels from creating new, synthetic fentanyl-like compounds to skirt the Controlled Substances Act.

Other speakers at Wednesday’s bill signing included Greg Swan, whose son died of a fentanyl overdose, and Anne Funder, who also spoke at last summer’s Republican National Convention about her son’s fentanyl-related death.

Trump has long railed against the flow of fentanyl into the U.S., using it as justification for imposing tariffs on Canada, Mexico and China.

He has complained that neither Mexico nor Canada is doing enough to stop the drug from crossing the border, though significantly more fentanyl crosses into the U.S. through the southern border than through the northern border.

The president has also hit China with tariffs over criticisms that the country is not taking enough action to stop fentanyl production.

Trump on Wednesday also touted his administration’s efforts to aggressively target drug cartels by designating them as foreign terrorist organizations.