Manchester City fans will not be allowed to wear belts inside the Stadio San Paolo for Wednesday night's Champions League game against Napoli.
The decision follows trouble around the two clubs' meeting in Manchester a fortnight ago.
A Napoli fan has been jailed for five months for his part in an attack in a pub near City's Etihad Stadium where belts were used as weapons.
The ban affects fans from both sides and will be in place in the stadium.
City are currently top of Group F having beaten Napoli 2-1 in the reverse fixture to go six points above the Italian side with three wins from three.