CNN  — 

All of Italy’s top football clubs have promised to do more to tackle its “serious problem” with racism.

The 20 teams in the country’s top division, Serie A, penned an open letter saying it was important to “publicly recognize” the issues facing the game after a number of incidents this season.

Recently, Brescia striker Mario Balotelli said he experienced racial abuse by opposition Verona fans and Inter Milan striker Romelu Lukaku was the subject of monkey chants from Cagliari fans earlier this season.

“We have to publicly recognize that we have a serious problem with racism. It’s a problem that we have not done enough to combat over the years,” read the letter, published on Friday.

“Images of players being racially abused in Italian football have been viewed and discussed all around the world this season and that shames us all.

“No individual should ever be subjected to racist abuse – inside or outside of football – and we can no longer stay silent on this issue or wait for it to magically disappear.”

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Portugal's forward Cristiano Ronaldo (L) speaks with Portugal's midfielder Joao Mario during the Russia 2018 World Cup Group B football match between Iran and Portugal at the Mordovia Arena in Saransk on June 25, 2018. (Photo by Jack GUEZ / AFP) / RESTRICTED TO EDITORIAL USE - NO MOBILE PUSH ALERTS/DOWNLOADS        (Photo credit should read JACK GUEZ/AFP via Getty Images)
Joao Mario on racism and Cristiano Ronaldo
03:01 - Source: CNN

Verona was given a one-match partial stadium closure following racist abuse aimed at Balotelli while Cagliari escaped any serious punishment for the racism aimed at Lukaku.

Serie A said it plans to set out its “comprehensive and robust” anti-racism policy which promised stricter laws and plans to educate people within the game.

“We don’t have any more time to waste,” the letter added.

“We must now act with speed, with purpose and with unity and we call on you, the fans, to support us in this vitally important endeavor.”

Racism has blighted European football this season, with other racist incidents in places such as Holland, Ukraine and on the international stage.

Last weekend, teams in the two top-flight divisions of Dutch football refused to play the opening minute of their games in a protest against racism.