TOKYO (AP) - FIFA president Sepp Blatter said Tuesday it was time to stop "refereeing experiments" at the World Cup and introduce a system that would help eliminate controversial referee calls.

Blatter said a new system should be established at the 2006 World Cup in Germany whereby every match will be officiated by a team of referees from one country who had worked together for at least two years.

"You can't have a World Cup filled with experiments," Blatter said in an interview with The Associated Press.

"Here we have a main referee from one country and he has two assistants from another country, and he's never worked with them before. That, in my opinion, is an experiment."

Blatter said World Cup games should be officiated by the "best referees in the world." He hinted that FIFA may have to abandon its policy of appointing referees from as many countries as possible.

"We'll have a trio of referees and obviously we'll have to look if they're from one country," he said. "Every trio of referees should have enough international exposure before being called on to officiate a World Cup match."

Complaints about dubious calls have plagued soccer's governing body since the Italians - eliminated in a second-round extra-time loss to South Korea - complained they'd been victimized throughout the World Cup.

Spain followed suit, slamming referees for disallowing three goals in the team's quarter-final loss to South Korea on penalties. On the second effort, replays clearly showed the ball had not gone out before it was crossed for Fernando Morientes to head home what would have been a golden goal.

"What has happened in these controversial decisions is that most of them were taken in the knockout rounds and you have no possibility to recover if you are victim of these errors," Blatter said, adding that most of the mistakes have been made by linesmen, not main referees.

On Monday, Blatter issued a statement denying there was a conspiracy to keep South Korea in the World Cup.

The tournament's referee chief joined Blatter on Tuesday in denying a conspiracy, saying he was annoyed the referees have had their "impartiality subjected to the most brutally unfair scrutiny."

"For referees there are no small teams and no big teams, there are no favourites and no outsiders. No referee would ever reach the pinnacle of his career, the World Cup, without complete integrity," said Senes Erzil, chairman of the referees' committee.

Canada had one official at this World Cup: Hector Vergara of Winnipeg, who worked several high-profile games without incident.