Germany on Wednesday condemned Iran over a contest for cartoons depicting the Holocaust, which opened on the weekend, saying it sows hatred and deepens divisions in the Middle East, according to The Associated Press.

The event was organized by non-governmental bodies with support from Iran’s hard-liners, though the government has distanced itself from the contest. The organizers of the exhibition insist that it is not meant to deny the Holocaust.

German Foreign Ministry spokesman Martin Schaefer said Wednesday that “the murder of 6 million men, women and children during the Holocaust, for which we Germans bear guilt and responsibility, must not be abandoned to ridicule.”

Schaefer said German Foreign Minister Frank-Walter Steinmeier made clear during a February visit to Tehran that no further such competition should take place, and that it was “very regrettable” it went ahead, according to AP.

UNESCO, the UN’s cultural body, on Sunday strongly condemned the contest, with its chief Irina Bokova saying, “Such an initiative which aims at a mockery of the genocide of the Jewish people, a tragic page of humanity’s history, can only foster hatred and incite to violence, racism and anger.”

“This contest goes against the universal values of tolerance and respect, and runs counter to the action led by UNESCO to promote Holocaust education, to fight anti-Semitism and denial,” she continued.

Iran has held Holocaust-denying cartoon exhibits before, notably last year when it announced the contest days after the terrorist attack on the offices of the Charlie Hebdo satirical magazine which had been attacked in the past over its caricatures of the Prophet Mohammed.

UNESCO has in the past condemned the contest, a fact which obviously has never prevented Iran from holding it again, nor has the condemnation prevented Iranian leaders from denying the Holocaust as part of their rhetoric against Israel.