The UN General Assembly condemned the denial of 'Holocaust' in which some 6 million Jews were exterminated by the Nazis during World War II.
In the resolution proposed by the US and co-sponsored by more than 100 countries on Friday, the 192-member General Assembly "urges all member states unreservedly to reject any denial of the 'Holocaust' as a historical event, either in full or in part, or any activities to this end.
"UN General Assembly resolutions are non-binding, unlike those of the 15-member UN Security Council, but carry moral and symbolic value.
The resolution is seen as a response to the recent Iranian sponsored conference in Tehran in which speakers questioned the Holocaust.
The resolution did not name Iran but the US and Israel wanted it to take note of the will of the international community.
However, Tehran stood by its stand that Holocaust should be closely examined to find out its scope.
In 2005 the United Nations proclaimed January 27 as the International Day of Commemoration in Memory of the Victims of the Holocaust to commemorate Jewish and other victims of the Nazi regime.
On this day in 1945, the Soviet Army had liberated the Auschwitz concentration camp from the Nazi control.
Speaking before the adoption of the resolution, Iranian delegate Hossein Gharibi said the Israel had manipulated the sufferings of the Jewish people as a cover for crimes committed against the Palestinians, including ethnic cleansing and state terrorism.