Evidence is growing that a British boycott of Israeli academics is gathering pace.
British academics have delivered a series of snubs to their Israeli counterparts since the idea of a boycott first gained ground in the spring.
In interviews with the Guardian, British and Israeli academics listed various incidents in which visits, research projects and publication of articles have been blocked.
Colin Blakemore, an Oxford University professor of physiology, who supports a boycott, said: "I do not know of any British academic who has been to a conference in Israel in the last six months."
Dr Oren Yiftachel, a left-wing Israeli academic at Ben Gurion University, complained that an article he had co-authored with a Palestinian was initially rejected by the respected British journal Political Geography. He said it was returned to him unopened with a note stating that Political Geography could not accept a submission from Israel.
Mr Yiftachel said that, after months of negotiation, the article is to be published but only after he agreed to make substantial revisions, including making a comparison between his homeland and apartheid South Africa.
The issue of a boycott was highlighted in the spring when two British academics, Steven and Hilary Rose, had a letter published in the Guardian supporting the idea. It was signed by 123 other academics.
Professor Paul Zinger, outgoing head of the Israeli Science Foundation, said: "Every year we send most of our research papers abroad for reference. We send out about 7,000 papers a year. This year, for the first time, we had people writing back, about 25 of them, saying 'We refuse to look at these'."