"He understands our position that it absolutely does have an impact, particularly on the folks who we are trying to reach out to and build unified communities," Tarrant said, recounting his conversation with Sessions.
Asked about the conversation between Sessions and NOBLE leaders, a Justice Department spokesman declined to comment.
Sessions had delivered a speech earlier Tuesday in Atlanta before NOBLE's annual training conference, in which he reaffirmed his commitment to "hold any officer responsible who violates the law."
"Just as I'm committed to defending law enforcement who lawfully have to use deadly force to defend themselves while engaged in their work, I will also use the powers of the office I've been entrusted with to hold any officer responsible who violates the law," Sessions said.
He added, in a line deviating from his prepared remarks, that "we'll probably talk a little bit about use of force and some of the policies that are important in that area" later.
Sessions' comments were his first public counterpoint to Trump's Long Island speech.
"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 Friday to scattered applause from a crowd of Long Island police officers.
Referring to officers shielding prisoners' heads with their hands, Trump added, "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?'"
NOBLE is among several law enforcement organizations that have rebuked the President's comments.
"The President's remarks a few days ago caused us a little bit of concern," Tarrant said Tuesday. "Whether intentional or unintentional it was heard around the country by the very communities that we're trying to build relationships with and I believe it had an impact."
On Monday, White House Press Secretary Sarah Huckabee Sanders said she believed the President was "making a joke at the time."
In his speech at the NOBLE conference, Sessions repeated his warnings of a spike in violent crime, likening Chicago and Baltimore to "killing fields" and underscoring the specific importance of the black police officers to whom he spoke.
"African-Americans have the least trust in police of any group in the United States," Sessions said, citing poll data that found 30% of African-Americans did not have confidence in police. "You, more than perhaps any other law enforcement organization, represent crucial ambassadors to some of the communities that trust law enforcement the least."