Jerusalem  - Sixty four years after the defeat of the Nazi regime and the end of World War II, anti-Semitism is still flourishing, Israeli President Shimon Peres warned Monday as he opened the country's annual commemoration of the Nazi's attempted genocide of the Jews of Europe.

"The gas has dissipated, but the poison remains. There are still Holocaust deniers and hot-headed skinheads in the world, those who bear the sort of visceral hatred that leads to racist murder," Peres said at the official ceremony at the Yad Vashem Holocaust Memorial Centre in Jerusalem.

The president also slammed the United Nations conference on racism which opened Monday in Geneva, and in particular the decision to allow Iranian President Mahmoud Ahmadinejad to address the delegates there.

"The conference opening today in Geneva constitutes an acceptance of racism, rather than the fight against it, and its main speaker is Ahmadinejad, who calls for the annihilation of Israel and denies the Holocaust," he said.

"A disgrace," he added angrily, echoing comments he and other Israeli spokesmen made throughout the day on the decision to give a platform at the anti-racism conference to Ahamdinejad, who has repeatedly denied the Holocaust and called for Israel's destruction.

Israel, Peres said, was "our historic victory over the Nazi beast that left no stone in Europe unturned.

"Soul-searching about the Holocaust is not yet over, and may never be over, not for us, and not for the world at large. Nazism was defeated, but anti-Semitism is still alive and well."

Prime Minister Benjamin Netanyahu, who spoke after Peres, also slammed the UN conference, describing it as a demonstration of hatred against Israel.

In a reference to both Ahmadinejad's statements that Israel should be wiped off the map and Israeli fears about Tehran's nuclear ambitions, he vowed that " we will not let Holocaust deniers perpetrate another Holocaust on the Jewish people."

The premier also singled out for Swiss President Hans-Rudolf Merz, whose meeting with Ahmadinejad led Israel to recall home its ambassador to Switzerland for consultations.

"I turn to you, the Swiss president, and ask you: How can you meet someone who denies the Holocaust and wishes for a new holocaust to occur?"

During the solemn service, six survivors lit six beacons, each commemorating a million Jewish victims.

Although the United Nations has designated January 27, the day the Auschwitz death camp was liberated in 1945, as international Holocaust remembrance day, Israel has traditionally marked it on the 27th day of the Jewish month of Nissan, one week before Independence Day, to symbolize the birth of the Jewish state from the ashes of the Holocaust.

As part of Israel's annual commemorations, a siren will also sound across the country at 10 am (0800 GMT) Tuesday and Israelis will stand at silent attention to honour the victims. Flags are flown at half mast throughout the day.

The names of the victims - or as many names as are known - will be read out at the Knesset and at Yad Vashem's Hall of Remembrance.

According to counts held before and after the war, two-third of Europe's nine million Jews perished at the hands of the Nazis and their collaborators.

One and a half million of them were children, the central theme of this year's commemorations. (dpa)