THE HAGUE (Reuters) - The United Nations human rights chief on Monday accused U.S. Republican presidential candidate Donald Trump of spreading "humiliating racial and religious prejudice" and warned of a rise of populist politics that could turn violent.

In comments at a security and justice conference, U.N. High Commissioner for Human Rights Zeid Ra'ad Al Hussein said he was addressing Dutch far-right leader Geert Wilders and other "populists, demagogues and political fantasists."

Naming Trump, Nigel Farage in Britain and Marine Le Pen in France, among others, he accused them of using "fear" tactics similar to those of Islamic State, also known as Daesh.

"Make no mistake, I certainly do not equate the actions of nationalist demagogues with those of Daesh," he said. "But in its mode of communication, its use of half-truths and oversimplification, the propaganda of Daesh uses tactics similar to those of the populists."

"History has perhaps taught Mr. Wilders and his ilk how effectively xenophobia and bigotry can be weaponized," he said. "The atmosphere will become thick with hate; at this point it can descend rapidly into colossal violence," he warned.

Zein called Wilders' election pledge to a ban Muslim immigrants and the Koran "grotesque".

Wilders is leading opinion polls ahead of March 2016 parliamentary elections in the Netherlands. Among his key campaign pledges are to close the country's border to Muslim immigrants, shut down mosques and ban the Koran. He also wants to leave the European Union.

(Reporting By Anthony Deutsch; Editing by Angus MacSwan)