Celtic have banned the Green Brigade from home matches after the prominent fan group defied the club’s request by displaying Palestine flags at last week’s Champions League game against Atletico Madrid. An email to supporters in the standing section has been published on social media showing that Celtic have suspended season tickets for those who have registered with the ticket office as being part of the ‘ultras’ group, who were already banned from away games as a result of a number of incidents this season. Wary of further Uefa disciplinary action, Celtic had asked fans not to bring any flags associated with the Middle East conflict ahead of facing Atletico at Celtic Park last Wednesday - but thousands defied the club’s appeal. An email leaked on social media shows Celtic cited "repeated incidents of unacceptable conduct involving the ‘Green Brigade’ group". The ban is pending further review and communication with the fans’ group. Celtic have been fined by Uefa twice this season for displays linked to the Green Brigade section - a pyrotechnic show away at Rotterdam and an "anti-fascist" banner which, according to the European governing body, contained a "provocative message of an offensive nature" towards Lazio. Other issues apparently cited by Celtic include "rushing turnstiles" at Fir Park, "illegally gained access" ahead of the Lazio match and "unauthorised banners" plus behaviour towards stewards. A Celtic spokesperson said: "To avoid any misunderstanding, the progressive steps taken by the club over a period of time are as a result of an increasingly serious escalation in unacceptable behaviours and non-compliance with applicable regulations, at matches at Celtic Park and away grounds over a period of time, which are creating serious safety concerns and other issues." Read More Celtic twice throw away lead as Atletico storm back to claim point Manchester United kit ‘too tight’ as players forced to wear replicas Police arrest 70-year-old man after alleged racist abuse during Barrow vs Morecambe