UN Secretary-General Antonio Guterres warned Friday that human rights "are under attack around the world" while praising those who defend them, during a ceremony marking the Universal Declaration of Human Rights' 75th anniversary.

"Inequalities are deepening. Hunger and poverty are rising. Women's rights are stalling, and in some cases, going into reverse," Guterres said at a ceremony marking the declaration adopted on 10 December 1948.

"Conflicts are raging, with appalling consequences for civilians as we are dramatically witnessing every single day with immense death and suffering in Gaza," he said.

And he added that "new threats are blossoming, from catastrophic climate disasters, to artificial intelligence, which holds the potential for immense possibility, but also for immense peril."

"And age-old hatreds are resurging with a vengeance -- from racism, to xenophobia, and religious intolerance."

"But across the world, human rights defenders are lights in the darkness," he said, calling their work "deeply dangerous."

Guterres said that in the past year, "almost 450 human rights defenders, journalists and trade unionists were killed. Forty percent more than the previous year."

The UN chief urged all member states to "strengthen their commitment to making human rights a reality."

The ceremony was joined by Anna Eleanor Roosevelt, chair of the board of directors of the Roosevelt Institute and granddaughter of the former US first lady who oversaw the drafting of the Universal Declaration of Human Rights.

She said her grandmother "wouldn't be pleased" with the status of the document these days.

"We must commit again and again to promote that moral force," she told the gathering.