The conference on Wednesday, sponsored by the World Jewish Congress and Israel’s mission to the U.N., focused on ways to combat the movement to boycott, divest from and sanction Israel. Sessions concerned opposing BDS on campus, among private corporations, on social media and at the U.N. itself — a body Israel and the United States have accused of being biased against Israel.

The conference also included a note of controversy, as a panelist accused attendees representing J Street of belonging to an anti-Semitic group.

Israeli U.N. Ambassador Danny Danon, opening the conference, criticized the U.N. Human Rights Council decision last year to create a so-called “blacklist” of companies that operate in Israel’s West Bank settlements.

“The halls of the U.N. are now being infiltrated by the boycott movement,” he said. He called the blacklist effort “pure anti-Semitism” and said that “together with the U.S., our greatest ally, we will keep fighting until BDS is eliminated.”

Earlier this month, a U.N. affiliate published a report accusing Israel of apartheid. But the report was removed from the internet soon afterward due to objections from U.N. Secretary General Antonio Guterres.

During a question-and answer segment at the day’s final session, a Jewish student representing J Street U, the campus arm of the dovish pro-Israel lobby, asked how students can best oppose BDS on campus while also opposing Israel’s occupation of the West Bank. South Carolina State Rep. Alan Clemmons, who has spearheaded legislative efforts to oppose BDS, responded by calling J Street anti-Semitic and rejecting the idea that the West Bank is occupied. He called Israel’s control of the territory an “eternal inheritance and legal right.”

“I personally believe that the organization that you’re representing is an anti-Semitic organization that chooses to ignore the law and chooses to ignore reality in order to push back on Israel in the Jewish community,” Clemmons said to loud cheers. “I stand by my words before that there is no illegal occupation.”

In her speech to in the General Assembly hall, Nikki Haley, the U.S. ambassador to the U.N., said BDS efforts as well as anti-Israel activity at the U.N. “seek to deny Israel’s right to exist.” Haley has promised to use her position to defend Israel at the United Nations.

“They are both efforts to intimidate her friends and embolden her enemies,” she said. “They are both extensions of an ancient hatred. And how tragic is it that, of all the countries in the world to condemn for human rights violations, these voices choose to single out Israel.”