The Cameroon striker tried to leave the pitch last Saturday after Real Zaragoza fans directed racist abuse at the player during their Primera Liga match.

Barca coach Frank Rijkaard and players persuaded him to finish the game, though the insults continued to the end.

"I wasn't at the game but I heard it on the radio and was ashamed. I was so outraged I decided to do something," Mayor Juan Alberto Belloch was quoted as saying in El Pais newspaper on Friday.

In his invitation letter to Eto'o he said: "I would like to offer you the chance to meet the people of my city. Zaragoza is a friendly, open, tolerant and multi-cultural place.

"I would like to show you and your family the preparations we are working on to host Expo 2008, which should be a symbol of respect to cultures across the world."

Real Zaragoza were fined 9,000 euros (10,750 dollars) by the Spanish Football Federation for the incident, but the government run Anti-Violence Commission said in a statement on Wednesday the fine was insufficient.

Eto'o suggested Zaragoza's stadium be shut for a year to set an example.