The leader of the Drug Enforcement Administration on Tuesday rejected President Trump's comments about police treatment of suspects, in a memo that said DEA agents must "always act honorably."

Chuck Rosenberg, the acting head of the DEA, sent a memo titled "Who We Are" to all agency employees on Saturday, and instructed them to discount any notion that law enforcement should use force against suspects, according to the Wall Street Journal.

"The president, in remarks delivered yesterday in New York, condoned police misconduct regarding the treatment of individuals placed under arrest by law enforcement," Rosenberg wrote in the memo.

Rosenberg said though he didn't believe any "special agent or task force officer of the DEA would mistreat a defendant," a response to Trump's comments was warranted.

"I write to offer a strong reaffirmation of the operating principles to which we, as law enforcement professionals, adhere," he said in the memo. "I write because we have an obligation to speak out when something is wrong. That's what law enforcement officers do. That's what you do. We fix stuff. At least, we try."

During a speech on the MS-13 gang before federal, state, and local law enforcement officials in Long Island last week, the president suggested officers shouldn't "be too nice" when arresting suspects.

"When you see these thugs being thrown into the back of a paddy wagon — you just see them thrown in, rough — I said, please, don't be too nice," Trump said. "Like when you guys put somebody in the car and you're protecting their head, you know, the way you put their hand over? Like, don't hit their head — and they've just killed somebody — don't hit their head. I said, you can take the hand away, OK?"

The president's comments were swiftly rebuked by a number of law enforcement agencies and police associations that said Trump's statements advocated the use of excessive force.

But White House press secretary Sarah Sanders said Monday the president was making a joke.