A leading British academic and member of the University and College Union warned over the weekend that the UCU's call for an academic boycott of Israel could seriously damage working relationships between UK and US universities and colleges. Prof. Mark Pepys, head of University of London's Department of Medicine and director of University College's Center for Amyloidosis and Acute Phase Proteins, made his statements after 300 presidents of US academic institutions declared their solidarity with Israeli institutions of higher learning. In a full-page advertisement in The New York Times, university and college presidents described the boycott as "intellectually shoddy and politically biased." Indicating that they would not work with institutions engaged in a boycott of Israeli academics, the advertisement said: "Boycott Israeli Universities? Boycott Ours, Too." "This is a matter of grave concern," Pepys. "The robust position of 300 US institutions in defense of the universally recognized principle of academic freedom cannot be ignored. American academia, with its depth, breadth and scale, has enormous impact in the UK at all levels of academic life. "There is now an immediate imperative for all British universities to take an equally rigorous and unequivocal public stand so that they are not tainted by association with those individuals who propose a boycott." Pepys urged academic institutions to follow the example of the London School of Economics and Oxford University, who recently announced their refusal to adopt a boycott. The New York Times advertisement comes after the director of a $150 million science foundation declared that applications from British researchers would no longer be accepted.