Arsenal striker Thierry Henry became the latest player to be targeted for verbal abuse during the Gunners' Champions League away win over PSV Eindhoven last Wednesday.

Liverpool and Fulham players have also been subjected to racial outbursts during European ties this season.

And Houllier said: "It is urgent that Uefa do something about it. Racial abuse is the worst form of lack of humanity.

"I have no respect for the people who do it, it's backward, something you could imagine 2000 years ago."

Henry said he plans to walk off the pitch if he is subjected to racist taunts again while playing for Arsenal.

Although Uefa immediately launched an investigation into the incident involving the prolific striker, Henry does not believe enough has been done to stamp out the problem.

"There is no place for racism in football and the authorities should be doing a lot more to deal with the problem," Henry told the Sunday People.

"If I walk off the pitch the next time this happens then people will take this problem more seriously.

"This is 2002 and you would have thought people's attitudes would and should have changed by now.

"I can handle the fans who try to wind you up. You get on with it and accept it. But why should I put up with racists?

"It sickens me when people feel they have a right to judge you by the colour of your skin."