Newcastle United have asked fans not to wear "traditional Arabic clothing or Middle East-inspired head coverings" at matches following the Saudi Arabian-led takeover of the club.
Some Magpies supporters wore the clothing when gathering outside St James' Park to celebrate the takeover.
Similar attire was also seen against Tottenham in the club's first home game under the new owners.
"No-one in the new ownership group was in any way offended," said the club.
"It was a gesture that was acknowledged as positive and welcoming in its intent.
"However, there remains the possibility that dressing this way is culturally inappropriate and risks causing offence to others.
"Newcastle United is kindly asking supporters to refrain from wearing traditional Arabic clothing or Middle East-inspired head coverings at matches if they would not ordinarily wear such attire.
"All visitors to the club are, as always, encouraged to wear whatever is the norm for their own culture or religion, continuing to reflect the broad and rich multicultural communities and groups from which the club proudly draws its support."
Newcastle, who parted company with manager Steve Bruce by mutual consent on Wednesday, play away at Crystal Palace on 23 October before their next home game against Chelsea on 30 October.
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