Dozens of right-wing demonstrators, including commentator Milo Yiannopoulos, gathered in New York on Thursday to protest against a university's decision to invite a Palestinian American activist to deliver a graduation speech next week.

The City University of New York's (CUNY) Graduate School of Public Health and Health Policy, which will have its commencement on Tuesday, described liberal, Muslim speaker Linda Sarsour on its website as a "powerful public health and social justice" leader.

'Despite our deep opposition to Sarsour’s views on Israel, we believe that she has a First Amendment right to offer those views' -Jonathan Greenblatt, ADL CEO

Protesters in midtown Manhattan chanted and marched under rainfall to criticise the school's choice of Sarsour, 37, an organiser of this year's Women's March on Washington who has drawn fire from conservatives for her opposition to Israel's occupation of the West Bank and Gaza Strip, among other issues.

Yiannopoulos, 32, said the Palestinian American organiser should be allowed to speak but should be held accountable for actions he considered anti-American.

"Working underneath all of that sweaty polyester is a mind that hates America," Yiannopoulos said of Sarsour, who wears a hijab.

Yiannopoulos was an editor at far-right news website Breitbart, but he resigned in February over comments that appeared to condone pedophilia.

'Working underneath all of that sweaty polyester is a mind that hates America,' Milo Yiannopoulos said of Sarsour (Reuters) Anti-Muslim zealot Pamela Galler also attended the demonstration, which was dubbed as an "anti-Sharia march".

In a letter published on Inside Higher Ed, five CUNY professors defended the decision to invite Sarsour to speak.

They said the Muslim American activist was selected because she "represents the new activism of young people, women, immigrants and others speaking out against discrimination and intolerance and in favor of democracy, solidarity and human rights".

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US Jewish civil rights group the Anti-Defamation League, which is pro-Israel, defended Sarsour's right to speak at the CUNY ceremony.

"Despite our deep opposition to Sarsour’s views on Israel, we believe that she has a First Amendment right to offer those views," ADL CEO Jonathan Greenblatt told The Jerusalem Post. "CUNY Chancellor Milliken shares in this belief, and recognizes that defending one's right to free speech does not equate to defending the content of that speech."

However, Michael D Cohen, a pro-Israel activist who graduated from CUNY, said inviting Sarsour to speak is damaging to the university.

He argued in an article published by Forward that Sarsour's appearance would "inspire only more hate, harassment and confrontations perpetrated against the Jewish student body," citing an event where she supported students opposing a measure to condemn the Boycott Divestment and Sanctions movement.

Demonstrations against both liberal and conservative speakers on university campuses has been a growing trend in the United States.

In April, conservative commentator Ann Coulter said she had scrapped plans to speak at the University of California at Berkeley in defiance of campus officials, who had barred her original engagement out of concerns about inciting violent protests.

In February, protesters at Berkeley started fires, broke windows and clashed with police, forcing Yiannopoulos to call off his appearance.

Yiannopoulos was permanently banned from Twitter for abuse and harassment of Saturday Night Live actress Leslie Jones in July 2016.