The Arsenal manager also backed his under-fire goalkeepers and promised the club would support Lukasz Fabianski following his two howlers which led to Arsenal's 2-1 defeat against Porto in the Champions League in midweek.

Wenger insisted Fabianski would play against Sunderland at the Emirates tomorrow if first-choice goalkeeper Manuel Almunia did not come through a fitness test on his injured finger.

But Wenger trained his fire on Europe's referees after reiterating his view that Hansson was wrong to allow Porto's second goal on Wednesday after giving an indirect free-kick in the box following a back pass by Sol Campbell which goalkeeper Fabianski picked up.

Wenger said: "It has to be clarified first of all how they nominate referees for games. They (UEFA) have to be much more open on how they rate their referees.

"Where is the ranking of the referees? I believe too much has gone on in the last 30 years. What has happened is not good for football."

When asked if Hansson, who missed Thierry Henry's notorious hand ball in France's World Cup qualifier against the Republic of Ireland, should be refereeing at Champions League level Wenger said: "I trust the referees to do their job and to do it well. I never ask who the referee is before a game but in this case I cannot say that he made everything right because he was wrong.

"It's not my job to judge is he good enough or not, I just feel in that game he has shown he is not competent.

"He made at least five technical mistakes for a referee. He made a massive mistake. You cannot give a quick free-kick once the referee is in the middle of the action.

"Once he is there in the middle, where the free-kick is, he cannot anymore give a free-kick, he has to make sure the opponent is at nine metres distance.

"I believe he is incompetent or dishonest, so I prefer to believe he is not competent."

Wenger also believes Portsmouth should not be allowed to sell players to solve their cash problems, instead preferring the Premier League to step in and bail them out from a "security fund".

Wenger said: "I feel for Portsmouth and I would like this club to be saved. For the reputation of the Premier League they have to go at least until the end of the season.

"Can they sell players out of the transfer window? I believe it would set a precedent that would be difficult to cover afterwards because every mis-management after any season could make the same request and we would be in a position where we could not forbid it.

"There should be a security fund available to save the competition at least. Afterwards, Portsmouth have to be punished at the end of the season for mis-management."

Wenger also insisted the proposal for a play-off system to be instituted for the Champions League fourth spot was a non-starter.

He said: "It is a very bad, bad, bad proposal because why should you question after 38 games what has been decided on the pitch?

"Secondly, who guarantees the fourth spot is available for the Champions League? Nobody. Tomorrow the Champions League rules can be changed and you have created a play-off situation with no object anymore. Nobody knows if the fourth spot will always be available."

William Gallas will be out for another fortnight with a calf injury and Campbell is set to to deputise again tomorrow. Alex Song is due to come in after Abou Diaby was ruled out with a knee injury.

Meanwhile, striker Robin van Persie is now not expected to be back from ankle damage until the end of April at the earliest.

On Fabianski, Wenger said: "He will be a great goalkeeper. He had an unlucky night. Every goalkeeper who had a great career has had a night like that.

"We have to show support to him and solidarity. It is a good opportunity for us to show that we are a special club and have a special togetherness. I believe in the keepers I have."