BERLIN, Jan 26 (Reuters) - Qatar's football association is suing former German soccer chief Theo Zwanziger for calling the Gulf nation a "cancer on world football" following its successful World Cup bid, Duesseldorf's regional court`said on Tuesday.

Zwanziger, who headed the German football association (DFB) until 2012, was asked in a television interview last year whether the decision to let Qatar host the 2022 World Cup should be reviewed as corruption allegations hit world soccer's governing body FIFA.

According to the court's statement, Zwanziger told public broadcaster Hessischer Rundfunk a review was "possible and necessary" and added: "I have always said that Qatar was a cancer on world football. It all started with that decision."

FIFA is facing the biggest crisis in its history with several investigations having led to 41 individuals and entities being indicted on corruption charges.

Switzerland's prosecutor is investigating both FIFA's decision to award the 2018 World Cup to Russia and the 2022 tournament to Qatar, a small, wealthy desert country with no real soccer tradition.

Qatar's FA said the remark by Zwanziger showed collective disrespect and was slanderous and he should not be allowed to repeat it, according to the court statement.

"The defendant claims that his remark was not aimed at one person or the Qatar Football Association but 'instead aimed at the awarding process through FIFA and the decision itself'," the court said.

There were no immediate statements directly from Qatar or Zwanziger. The case is due to start on Feb. 2.

A Frankfurt prosecutor is also formally investigating Zwanziger and two other former football officials for suspected tax fraud in relation to a payment to FIFA relating to the 2006 World Cup in Germany.

(Reporting by Karolos Grohmann; Editing by Ed Osmond) ((karolos.grohmann@thomsonreuters.com; +491743343192; Reuters Messaging: karolos.grohmann.thomsonreuters.com@thomsonreuters.net;))

Keywords: SOCCER WORLD/QATAR ZWANZIGER