Cambridge University students have launched a campaign to block the visit of former IMF chief Dominique Strauss-Kahn to one of the country's oldest debating chambers.

Mr Strauss-Kahn, who resigned from his post last year amid allegations of sexual assault, and who more recently was questioned by police about his involvement in a prostitution ring, is due to speak about economic policy at the Cambridge Union on March 9.

But his presence at the union has provoked a heated debate on the balance between free speech and the welfare of students.