Ronny Deila has urged the "one percent" of troublesome Celtic fans to behave ahead of the Europa League clash with Inter Milan at the San Siro on Thursday night.
UEFA's Control, Ethics and Disciplinary Body announced today that the Parkhead club have been fined 10,000 euros (approximately 7,300 pounds) following crowd disturbances at their Europa League match with Dinamo Zagreb last year.
It is the sixth time in just over three years that European football's governing body has taken action against the Scottish champions and it comes as around 3,000 fans are expected to make their way to the San Siro for the second-leg of the last-32 clash against the Serie A giants, which is tied at 3-3 from the first leg at Celtic Park last week.
"You saw last Thursday what the Celtic fans could be and the atmosphere in the stadium was unbelievable," said the Hoops boss.
"That is something to be proud of.
"We have a good support all over Europe when we play and 99 per cent of them are acting and behaving in a very good way.
"Sadly, we have one per cent who haven't done that and have made problems.
"It is so important for us in the future that we stop this and get known as good supporters and as I said, last Thursday was just world class in my opinion."
Assistant manager John Collins believes the club have to "weed out" the transgressors.
He said: "We are obviously disappointed. We had 60,000 last week and it was unbelievable behaviour from every one of them and that is what Celtic is all about.
"One or two [are] causing problems and hopefully that is the last we hear of it.
"They are representing a wonderful football club and throughout the years the vast majority of them have been impeccably behaved and we have a great reputation throughout Europe.
"But one or two we have to try to weed out."
A club spokesperson told Celtic's official website: "Clearly everyone is extremely disappointed that the behaviour of only a handful of people and in particular the use of flares, have led to a further fine from UEFA.
"We have repeatedly called for the use of flares to stop. We cannot and will not allow the safety of our supporters or the reputation of our great club to be compromised by the actions of a tiny minority.
"It is time those responsible understand the damage this does to the club they claim to support."