The United Nations Educational, Scientific and Cultural Organization (UNESCO) recently filed a serious complaint with the Iranian government over its plan to hold a cartoon contest promoting Holocaust denial, Haaretz reported Monday.

According to the newspaper, UNESCO director-general Irina Bokova plans to raise the issue when she meets Iranian President Hassan Rouhani who will be addressing the organization’s staff this coming Wednesday, which is International Holocaust Remembrance Day.

On December 17, Iran’s IRNA news agency announced a contest for satirical cartoons relating to the Holocaust, to take place in June in Mashhad as part of the Teheran International Cartoon Biennial that has been held for the past 11 years.

The winner of the contest will get a prize of $50,000, and organizers told the agency that the contest was not a display meant to deny the Holocaust or support it, but to enable questions to be asked about it.

Israel’s Ambassador to the UN, Danny Danon, two weeks ago called on UN Secretary General Ban Ki-moon to condemn Iran for hosting the contest.

“This anti-Semitic act represents the pure evil of the Iranian regime,” Danon said, adding, “Denying the Holocaust is one of the most powerful expressions of anti-Semitism, which legitimizes the deaths of millions of Jews.”

“The United Nations must resolutely stand up against this hatred and harshly condemn this heinous act,” he wrote to Ban.

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.

Haaretz noted, however, that the announcement of this year’s contest attracted considerable attention, coming only a month before the nuclear agreement with Iran and the removal of sanctions against it went into effect.

Reports on the contest were published in the West two weeks before Rouhani’s tour of European capitals which began on Monday in Rome and continues in Paris, the newspaper noted.

On January 4, following the reports in the Iranian press, Israel’s envoy to UNESCO, Carmel Shama-Hacohen, wrote to Bokova to bring the planned contest to her attention. UNESCO conducts activities throughout the world to preserve the memory of the Holocaust, combat anti-Semitism and promote Holocaust education.

“I urge you to condemn this contest and the Iranian authorities who enable it,” Shama-Hacohen wrote to Bokova, in a letter obtained by Haaretz. “It is incumbent to condemn this severe act of Holocaust denial, which badly offends the victims and survivors. It is time for UNESCO to demand accountability from the Iranian regime with regard to its malicious rhetoric, Holocaust denial and global negative activity.”

On January 15, Bokova responded, telling Shama-Hacohen that she was “deeply outraged” when she heard that once again Iran was holding a contest, “which makes a mockery of the darkest chapter in the history of humanity.”

Bokova wrote that the cartoon contest would only “further serve to incite hatred, racism, and discrimination. This goes against the objectives pursued by UNESCO to promote greater understanding and knowledge about the Holocaust.”

In her letter, a copy of which also reached Haaretz, she condemned the contest, saying she had sent a letter about the contest to the Iranian envoy to UNESCO in which she had expressed her deep concern.

“I believe that all UNESCO action has never been so important than in these times of turbulence, as we face the rise of violent extremism and barbarous acts of hatred and anti-Semitism,” wrote Bokova.

Bokova has yet to issue any public condemnation of the cartoon contest, according to Haaretz, preferring instead to convey her message by diplomatic channels to both Shama-Hacohen and the Iranian delegate. But during Rouhani’s planned visit to UNESCO headquarters on Wednesday, she is expected to register her protest of the contest to the Iranian leader.

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.

In 2014, Iran’s Supreme Leader Ayatollah Ali Khamenei suggested that the Holocaust “was not real”.

Khamenei is not the only Iranian leader to have denied the Holocaust. Former President Mahmoud Ahmadinejad did so on a regular basis and, prior to leaving the presidency, he he prided himself most on his denial of the Holocaust.

Current President Hassan Rouhani told CNN shortly after assuming office that the Nazis committed a “reprehensible” crime against the Jewish people, but Iran subsequently claimed that the network had misrepresented Rouhani’s statements.