New Orleans Saints quarterback Drew Brees has come under fire from athletes such has LeBron James after he said he will “never agree with anybody disrespecting the flag of the United States” when asked about the prospect of NFL players kneeling for the national anthem during the upcoming season.

Brees reiterated his opposition to the non-violent protest of police violence launched by Colin Kaepernick during the 2016 season in an interview with Yahoo Finance published on Wednesday, his first remarks since last week’s police killing of George Floyd.

“I will never agree with anybody disrespecting the flag of the United States of America or our country,” the future Hall of Famer said. “Let me just tell what I see or what I feel when the national anthem is played and when I look at the flag of the United States.

“I envision my two grandfathers, who fought for this country during world war two, one in the Army and one in the Marine Corps. Both risking their lives to protect our country and to try to make our country and this world a better place. So every time I stand with my hand over my heart looking at that flag and singing the national anthem, that’s what I think about.”

Brees’s comments drew immediate criticism from one of his highest-profile teammates, Pro Bowl wide receiver Michael Thomas, who tweeted: “He don’t know no better.”

Said Thomas in a subsequent post: “We don’t care if you don’t agree and whoever else how about that.” Another of Brees’ teammates, Malcolm Jenkins, posted a video to social media in which he came emotional as he said the quarterback did not understand the struggle of black people in America.

Stars from other sports also joined in with the criticism. LeBron James, arguably the most high-profile athlete in America, posted his thoughts on Twitter.

“You literally still don’t understand why Kap was kneeling on one knee??,” wrote the LA Lakers star on Twitter. “Has absolute nothing to do with the disrespect of [America] and our soldiers( men and women) who keep our land free. My father-in-law was one of those

Brees, 41, offered a clarification of his initial remarks in a statement to ESPN.com, though he refused to back down on his stance.

“I love and respect my teammates and I stand right there with them in regards to fighting for racial equality and justice,” Brees said. “I also stand with my grandfathers who risked their lives for this country and countless other military men and women who do it on a daily basis.”

Brees’s remarks came one day after Sean Payton offered an impassioned take on social media that Floyd and Ahmaud Arbery were “murdered not killed” and calling for change in the November elections.

Brees is considered one of the finest quarterbacks in NFL history. He is the league’s all-time leader in passing yards and touchdowns.