Mr Makanji, who is not a judge but had been chosen around a month ago to sit as a lay member of the panel, was asked to recuse himself from the case by Daniel Lightman QC, who was representing Julian Hunt.
Mr Hunt, a director of the UK Lawyers for Israel group, had appealed against an earlier decision by Elizabeth Denham, the Information Commissioner, who had backed King’s College London’s refusal to reveal details to Mr Hunt regarding the violent scenes on its campus.
Mr Hunt had used the Freedom of Information Act to attempt to find out how many students had been disciplined after the protests in January last year. King’s decided not to take part in the appeal hearing in central London.
Police were called to the campus after pro-Palestinian activists smashed a window, threw chairs and set off fire alarms as around 100 people attempted to hear Ami Ayalon, the former head of Israel’s Shin Bet, deliver a lecture.
One student who was present said the room had been “ambushed… it was really quite frightening”.
King’s investigated and found that those who carried out the disruption “chose to behave inappropriately, crossed a line and should be held accountable for doing so”.
One protestor was later found guilty of assault by beating in the criminal courts.
Mr Lightman this morning told the tribunal Mr Makanji could be accused of bias if he was allowed to sit on the case.
Following a discussion, Brian Kennedy, the tribunal judge, said Mr Makanji had recused himself.
The one-day hearing was postponed and will take place at a later date.
In a tweet during the Gaza conflict in 2014, Mr Makanji asked: "Israel calls up 16k reservists to buttress IDF. How many will be citizens of USA & UK? # genuinequery"
Mr Hunt said UK Lawyers for Israel had been waiting for "several months" for an "impartial and fair tribunal".
"This was a case of the utmost political sensitivity. All parties, including the Information Commissioner, had worked hard to prepare for today’s hearing.
"At about 6 pm on Friday evening I received the names of the members of the tribunal who were due to hear my appeal.
"On Saturday evening I discovered that Narendra Makanji, one of the three members of the panel, has tweeted in support of the BDS movement against Israel, and has previously called for the expulsion of the then Israeli Ambassador Daniel Taub, amongst a host of other anti-Israel comments.
"I was shocked to see that his latest BDS tweet had occurred just nine days before this hearing was due to take place, after he had been appointed to hear this case."
Mr Hunt said he was "dismayed" Mr Makanji had not recused himself as soon as he was assigned to the case.
"I am deeply disturbed by the thought that had I not looked up this person online, he would have sat in a judicial capacity throughout the hearing."
Jonathan Turner, chair of UK Lawyers for Israel, said: "Other London universities have told us that no students were disciplined by them for the riot which forced the termination of the joint meeting of KCL’s and LSE’s Israel Societies with Ami Ayalon, even though KCL’s investigation identified several students from other universities who participated in the disruption.
"KCL itself refused to disclose the number of students that it had disciplined, and what sanctions, if any, were imposed, on the grounds that this might enable the students to be identified and that this would be unfair.
"We remain very concerned that some universities are not doing nearly enough to ensure freedom of speech on campus for pro-Israel speakers. Instead of punishing the students who organised the riot, KCL appears to have imposed restrictions on activities of its Israel Society in order to avoid trouble."
A judiciary spokesman confirmed that following an application by the claimant, Mr Makanji had recused himself from the hearing. The spokesman said the tribunal was liaising with the parties to find a suitable date for the hearing to take place.
