Celtic have been fined £8,616 by UEFA after fans displayed an "illicit banner" during their recent Champions League qualifier against Hapoel Be'er Sheva.
Fans flew Palestine flags before and during the match against Israeli opposition at Parkhead on Aug. 17, resulting in a charge from European football's governing body.
UEFA viewed the flags as illicit banners under Article 16 of its disciplinary regulations and at a disciplinary hearing the complaint against the Scottish champions was upheld and the club were fined.
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."
Celtic have been punished eight times in five seasons by UEFA for supporter misconduct and the sanction on each occasion has been a fine from the governing body.
They were fined around £16,000 two years ago after a Palestine flag was displayed at a Champions League qualifier against KR Reykjavik.
Last month, some fans of the club launched an online campaign in a bid to raise funds for Palestinian charities, with the aim of matching the fine imposed by UEFA. The fundraiser has since collected in excess of £100,000 in donations.