The University of Manchester’s student union (UMSU) has passed an Israel boycott motion, in what has been described as a “great injustice".

Lawrence Rosenberg, a former Manchester JSoc president and director of campus operations for the Pinsker Centre, an Israel advocacy group, was present at the meeting last Thursday at which the motion was proposed and passed.

He described it as "one of the greatest injustices I have ever witnessed".

"I watched masses of Jewish students plead for positive dialogue on the Israel-Palestine conflict”, the modern history and politics student later wrote in a public Facebook post.

“I watched them plead for representation from a union which claims to have their interests at its core and, most disgracefully, I watched them beg for their safety on campus, something no student regardless of their background should ever have to do. I then watched their pleas turned down.”

Mr Rosenberg told the JC pro-Israel students “found out that that this motion was going to be proposed to the [union] senate about a week to 10 days before.

“In that time, we had to work out what was in the motion and how we could oppose it. We tried to oppose an amendment and then we weren’t allowed to amend it – we didn’t have a lot of time.”

Mr Rosenberg confirmed the motion, having been passed by the senate, was “still being processed by the [union] trustees".

“They are currently taking legal advice, and we hope that they see that the motion is illegal,” he said.

“We’re giving them due process and time to make a proper decision on the legal position they’re going to take.”

In a statement released by the Union of Jewish Students, the organisation said it was “extremely disappointed that students on Manchester students’ union’s Senate voted to reject peace, dialogue, and coexistence, in favour of a divisive BDS campaign that left many Jewish students present in a state of distress".

A spokesperson for UK Lawyers for Israel confirmed the group was aware of the motion.

“We have warned the student union and the university that the policy is illegal, as well as damaging to the University of Manchester by confirming its reputation as a hostile campus for Jewish students,” the spokesperson said.

“We intend to pursue our concerns with the appropriate authorities.”

A Manchester University students' union spokeswoman said: “While a very emotive subject, the motion was conducted and facilitated in a fair and inclusive environment in accordance with our core values.

“Regarding the implementation of the motion, we cannot yet act on the boycott, divestment and sanctions from Israeli companies, and as such the Trustee Board will consider how the policy will be applied early in 2017.”

A spokesman for the University of Manchester subsequently confirmed that the Student Union's motion was "not the position of The University of Manchester", and that "The University and UMSU are separate legal entities."