President Donald Trump. (AP)

(CNSNews.com) -- Speaking before a prominent group of police chiefs and sheriffs from across the nation, President Donald Trump said his administration will fight a "ruthless" war against illegal drugs and assist state and local officials in stopping gang members, "many of whom are not even legally in our country."

"I've been here two weeks," President Trump said of his administration before a gathering of the Major Cities Chiefs Association (MCCA) in Washington, D.C. on Feb. 8. "I've met a lot of law enforcement officials."

"Yesterday, I brought them into the Oval Office," he said. "I asked a group, what impact do drugs have in terms of a percentage on crime? They said, 75 to 80 percent. That's pretty sad."

"We're going to stop the drugs from pouring in," said the president. "We're going to stop those drugs from poisoning our youth, from poisoning our people. We're going to be ruthless in that fight. We have no choice."

As for the drug cartels that have operatives throughout the United States, President Trump said "we're going to take that fight to the drug cartels and work to liberate our communities from their terrible grip of violence. You have the power and knowledge to tell General [John] Kelly -- now Secretary Kelly -- who the illegal immigrant gang members are."

"Now, you have that power because you know them, you're there, you're local," said Trump. "You know the illegals, you know them by their first name, you know them by their nicknames. You have that power. The federal government can never be that precise. But you're in the neighborhoods -- you know the bad ones, you know the good ones."

He continued, "I want you to turn in the bad ones. Call Secretary Kelly's representatives and we'll get them out of our country and bring them back where they came from, and we'll do it fast. You have to call up the federal government, Homeland Security, because so much of the problems -- you look at Chicago and you look at other places."

"So many of the problems are caused by gang members, many of whom are not even legally in our country," said Trump. "And we will work with you on the frontlines to keep America safe from terrorism, which is what I began this with."