Napoli sports chief Riccardo Bigon says they're actively seeking to strengthen coach Walter Mazzarri's squad this summer.

Napoli qualified for the Europa League and could aim even higher next season, but Mazzarri has complained the squad is too large.

"There is still some work to be done and we'll try to give the Coach a squad that suits his needs," said Bigon.

"Now there is a delicate week ahead of us, as the co-ownership deals go into their final negotiations."