UEFA said Scottish football club had been charged for displays of an "illicit banner"
UEFA have opened disciplinary proceedings against Celtic after a section of their support displayed Palestinian flags during Wednesday's Champions League play-off first leg against Hapoel Beer-Sheva of Israel.
European football's governing body said Celtic had been charged for displays of an "illicit banner". It added, "this case will be dealt with by the UEFA Control, Ethics and Disciplinary Body on 22 September."
The UEFA rule in question forbids the use of "gestures, words, objects or any other means to transmit any message that is not fit for a sports event, particularly messages that are of a political, ideological, religious, offensive or provocative nature".
Dozens of Palestinian flags were displayed during Celtic's 5-2 first-leg win, many of them in the new safe standing section at Parkhead.
Celtic were fined about $20,900 two years ago after a Palestine flag was displayed at a Champions League qualifier against KR Reykjavik of Iceland.
Thus far, the European governing body punished the Scottish champions eight times in five seasons for supporter misconduct.
The second leg of the play-off tie will be played in Israel next Tuesday, August 23.