The Simon Wiesenthal Center expressed concern Tuesday over the possibility that Iran's hard-line president might attend the World Cup in Germany and urged Berlin to declare him "persona non grata." President Mahmoud Ahmadinejad has drawn international outrage for labeling the Nazi Holocaust a myth and calling for Israel's destruction. He has not said whether he will travel to the World Cup, where Iran is one of the 32 teams competing. The German government has said a visit would be problematic but that, like other heads of state, he has a right to attend. The Simon Wiesenthal Center urged the government to keep Ahmadinejad out in a letter to Foreign Minister Frank-Walter Steinmeier. "After his denial of the Holocaust, his calls 'to wipe Israel off the world map,' his encouragement to global terrorism and his nuclear threats, President Ahmadinejad should not be welcome in Berlin," the letter said, according a statement from the European office of the Los Angeles-based organization. The center "urged that Iran's president be declared persona non grata ... from German soil until he desists from such behavior that violates the norms of international relations," the statement added. Germany, which has sharply criticized Ahmadinejad's comments on Israel and the Holocaust, also is among countries leading diplomatic efforts to resolve concerns over Iran's nuclear program. Over the weekend, Wolfgang Bosbach, a senior member of Chancellor Angela Merkel's Christian Democrats, said the government should "make clear in a diplomatic way that Ahmadinejad's visit in Germany is not wanted."