Former San Francisco 49ers quarterback Colin Kaepernick started the silent protest by kneeling during the national anthem before each football game, to raise awareness of what he feels are the social injustices that people of color endure daily.
"The President has asked for a list of supporters who stand for the National Anthem".
Goodell said later that "We're going to encourage our players to stand".
Goodell also said there were only "six or seven" players protesting.
Later, NFL commissioner Roger Goodell repeated his stand that he wants players to stand during the national anthem, but no rule forcing them would be created and the league would not issue punishments for not doing so, USA Today reported. "We spent today talking about the issues that players have been trying to bring attention to - issues to make our communities better. that was the entire focus of today". The meeting between owners and players ended with no agreement on the thorny issue of protests during "The Star-Spangled Banner", which has bitterly divided the sport and fans of the game. It was the most recent in a series of semi-regular rebukes since he first expressed his disdain for the protests at a rally in September.
President Trump supported the idea of the NFL simply banning protests during the national anthem.
Former San Francisco 49ers quarterback Colin Kaepernick, who first popularized the gesture a year ago, said he settled on kneeling as a form of protest because it is widely seen as a gesture of respect.
Last weekend, players and coaching staff at German soccer team Hertha Berlin kneeled during their league match against Schalke, to show support for "an open-minded world".
More players have begun kneeling since Trump criticized the practice, and some sympathetic teammates have linked arms with the kneelers while standing themselves. The players then stood for presentation of Great Britain's anthem "God Save the Queen". Instead, he said, the team owners generally agreed it was important to listen to players' concerns.