BDS founder Omar Barghouti will not attend a Labour Party Conference fringe events in Brighton next week after what Palestinian supporters in the UK called an “abnormal” visa delay.

Barghouti, a Qatari-born Palestinian, grew up in the United States and studied at Tel Aviv University, before co-founding the Boycott, Divestment and Sanctions (BDS) movement by publishing a book of the same name in 2011.

He was invited to attend this week’s conference by the National Education Union, whose general-secretary Kevin Courtney reacted angrily to the news.

“We invited Omar Barghouti at a crucial time when global solidarity with the Palestinian people is needed more than ever,” he said.

“We cannot see any valid reason why his visa application would be delayed and call on the UK Government to uphold its responsibilities to freedom of movement and expression.”

Barghouti had been due to speak at a fringe event hosted by the Palestine Solidarity Campaign (PSC) alongside Shadow Home Secretary Diane Abbott, Unite General Secretary Len McCluskey and Labour MP Lisa Nandy.

PSC chair Kamel Hawwash said it was “an attempt to silence Palestinian voices and suppress activism,” adding: “This abnormal [visa] delay… comes in the context of statements by ministers expressing their intention to suppress UK support for the Palestinian-led BDS movement. Omar’s voice will be heard.”