U.S. Soccer has passed a new rule requiring “all persons representing a Federation national team” to stand respectfully during the playing of the national anthems before any event where the national teams are involved.

The rule was passed last month but came to light on Saturday in a tweet from FOX Soccer’s Stuart Holden.

New Policy added to @ussoccer bylaws: Players "shall stand respectfully during playing of national anthem @ which federation is represented" pic.twitter.com/fkVtCI1iHC — Stuart Holden (@stuholden) March 4, 2017

In an ensuing Twitter exchange with SI’s Grant Wahl, Holden cited US Soccer president Sunil Gulati in saying there are no preset consequences for not standing during the anthems and that consequences would be addressed on a case-by-case basis.

The notion of not standing during national anthems was rarely if ever an issue until last summer when San Francisco 49ers’ quarterback Colin Kaepernick sat on the bench in protest before a preseason game. Kaepernick later amended his protest to kneel and Megan Rapinoe followed suit by kneeling before the Seattle Reign’s match against the Red Stars on September 4. After the match Rapinoe said it was a “nod to Kaepernick” who said he was trying to move the discussion of race relations forward by kneeling. Rapinoe later took a knee while playing for the U.S. afterwhich U.S. Soccer released a statement saying they expected players to stand and honor the flag during the national anthem.

Rapinoe has not been in with the U.S. since January camp which concluded before the new rule was passed.