The Euro 2012 football championships have been marred by racism before they have even begun.

For months the much-anticipated tournament has been discussed in light of concerns over host nations Poland and Ukraine's right wing "ultra" fans' racist behaviour.

At an open training session in Krakow, Poland, Dutch players were subjected to monkey chants with Holland captain Mark van Bommel branding the incident "a real disgrace".

Governing body of European football, Uefa, today vowed to crack down on racism at the championships after acknowledging the abuse which happened at Wisla Krakow's Miejski Stadium.

Uefa confirmed they would consider increasing the number of stewards at open training sessions in order to eject fans if there was a repeat incident.

They said in a statement: "Uefa has now been made aware that there were some isolated incidents of racist chanting that occurred at the open training session of the Dutch team.

"Uefa has not yet received any formal complaint from the KNVB (Dutch football association).

"Should such behaviour happen at further training sessions, Uefa would evaluate the operational measures to be taken to protect the players.

"Uefa has a zero-tolerance policy when it comes to discriminatory behaviour and has given the power to referees to stop matches in case of any repeated racist behaviour."