Foreign academics have thrived at St Andrews University: Louise Richardson was principal and the physicist Jim Scott is a professor Getty Images

A “brain drain” of leading academics has begun already, four months after the Brexit vote, universities have told The Times.

It mirrors the intellectual flight of the early 1980s, which resulted in top British researchers basing themselves in America. Many are now Nobel prizewinners.

Elite British universities are paying for visa fees and legal advice for academics from abroad, in an attempt to hold on to them. Some who have left for other countries have taken millions of pounds in research funding and their postdoctoral students with them.

Anna Soubry, the Conservative MP and former business minister, told the Commons this week that the best EU workers were leaving the University of Nottingham, and academics from the school of geographical sciences at the University of…