Washington - US President Barack Obama marked Holocaust Remembrance Day on Thursday by warning that preventing genocide in the future depends on the world's willingness to confront hatred wherever it arises.

"Bearing witness is not the end of our obligation. It's just the beginning. We know that evil has yet to run its course on earth," Obama said. "We've seen it, in this century, in the mass graves and the ashes of villages burned to the ground and children used as soldiers and rape used as a weapon of war."

Obama spoke during a ceremony in Congress to remember the 6 million Jews who died at the hand of Nazi Germany during World War II and to honor Holocaust survivors.

Obama said the lesson of history demands a stronger response from the international community, pointing to the ongoing conflict in Sudan's Darfur region widely regarded as a genocide.

"Today and every day we have an opportunity as well as an obligation to confront these scourges, to fight the impulse to turn the channel when we see images that disturb us or wrap ourselves in the false comfort that others' sufferings are not our own," he said.

Obama also targeted those who trivialize or deny the Holocaust took place, but without mentioning Iranian President Mahmoud Ahmadinejad, who is frequently the focus of international criticism for questioning the Holocaust.

Ahmadinejad just last week referred to Israel as a "racist regime" at a UN conference in Geneva, but refrained from controversial comments he has made earlier in his term about the Holocaust.

"To this day, there are those who insist the Holocaust never happened, who perpetrate every form of intolerance, racism and anti- Semitism, homophobia, xenophobia, sexism, and more, hatred that degrades its victim and diminishes us all," Obama said.

Obama himself has been under pressure to declare that the slaughter of Armenians that began in 1915 under the Ottoman Empire was a genocide. He pledged to do so during the campaign, but has not taken the step since taking office, disappointing the Armenian- American community.

Obama is expected to release an annual presidential statement on Friday, which is regarded as the 94 anniversary of beginning of the killing of an estimated 1.5 million Armenians from 1915 to 1923.

Obama said during a trip to Turkey this month that he does not want to take steps that could jeopardize the ongoing negotiations between Turkey and Armenia to normalize relations, of which the genocide issue is a key part. (dpa)