UNITED NATIONS — French philosopher Bernard-Henri Levy challenged the world at the first-ever U.N. General Assembly meeting devoted to anti-Semitism to counter the rising hatred of Jews, which he denounced as "radical inhumanity."

In a keynote address on Thursday, Levy decried that "faulting the Jews is once again becoming the rallying cry of a new order of assassins."

The United Nations was established on the ashes of the Holocaust after World War II, and one reason was to fight the "plague" of anti-Semitism, Levy noted.

The assembly was held in response to the global increase in violence against Jews and was scheduled before the killing of four French Jews at a kosher market during three days of terror in Paris earlier this month. Paris was just the latest attack to raise fears among European Jews, following killings at a Belgian Jewish Museum and a Jewish school in southwestern France.

A surprise speaker was Saudi Arabia's Ambassador Abdallah Al-Moualimi, who told the meeting that Islamic countries condemn all words and acts that lead "to hatred, anti-Semitism, Islamaphobia."

Levy called for new arguments to counter those who say "Jews are detestable" because they support the "illegitimate state" of Israel, because they deny the Holocaust, and because they want their victims to overshadow other people's martyrs including the Palestinians.

"It is up to you who are the faces of the world to be the architects of a house in which the mother of all hates would see its place reduced," said Levy, who is Jewish. "May you in a year's time, and in years after that and every other year, reconvene to observe that the mobilization of today was not in vain."

U.S. Ambassador Samantha Power urged the world to stand up against anti-Semitism and take action to end "this monstrous global problem" She noted that even in the United States, nearly two-thirds of religion-driven hate crimes in 2012 targeted Jews, according to an FBI report.

"When the human rights of Jews are repressed, the rights of other religious and ethnic groups are often not far behind," she warned. "If we fail to expand dramatically the ranks of those fighting anti-Semitism, not only will be fail in our obligations to the Jewish people, but we will see the weakening in our own societies of the rights and bonds that tie us all together."

German Minister of State for Europe Michael Roth warned that "anti-Semitism is gaining ground in a loud and aggressive manner" and posed a threat to society as a whole.

Because of Germany's role in the Holocaust, he said, his country will always be in the forefront of fighting anti-Semitism and pursuing "a zero-tolerance policy."

Al-Moualimi, the Saudi ambassador who spoke on behalf of the 57-nation Organization of Islamic Cooperation, emphasized the parallels between anti-Semitism and Islamaphobia.

"We have witnessed with growing concern the increase in hate crimes around the world, and we are very concerned because some arbitrarily reject their responsibilities in this regard," Al-Moualimi said. "Anti-Semitism and Islamaphobia and all crimes that are based on religious hate are inextricably linked, they're inseparable."

He said Israel's occupation of Palestinian territory, which he called "an anti-Semitic act" that "threatens humankind," along with political crises, economic recession and policies that protect powerful nations "are very closely linked to the increase in hate crimes, extremism, and violence and anti-Semitism." The only way to address this increase and fight terrorist groups is to develop a strategy that focuses on dialogue, Al-Moualimi said.

The U.N. meeting was informal, and about half the 193-member states did not attend, but nearly 50 countries were slated to speak.

A panel discussion in the afternoon will include U.S. and Canadian lawmakers and several human rights experts including an Israeli professor.

Assembly spokesman John Victor Nkolo said the 193-member world body has discussed anti-Semitism many times in sessions dealing with intolerance, xenophobia, violence, racism and human rights violations. But he said "based on the available records we were able to check, this is indeed the first time that anti-Semitism as such is specifically the subject of an informal meeting of the U.N. General Assembly."

The meeting was requested by 37 countries who sent a letter to assembly President Sam Kutesa on Oct. 1 calling for a meeting in response to "an alarming outbreak of anti-Semitism worldwide." They said they wanted a meeting because "a clear message from the General Assembly is a critical component of combatting the sudden rise of violence and hatred directed at Jews."

The letter noted Secretary-General Ban Ki-moon's statement last Aug. 3 expressing concern at the spike in anti-Semitic attacks.

"At rallies, crowds have chanted 'Gas the Jews" and 'Death to the Jews,'" it said. "Firebombs have been thrown at synagogues and Jewish-owned businesses have been vandalized."