Samajwadi Party (SP) chief Mulayam Singh Yadav's visit to Aligarh Muslim University to address a seminar was cancelled today after widespread protests on the campus, though no reason was given for the decision.br br There were protests on the campus by a section of teachers in the past two days after it was announced that Mr Yadav had been invited to address the seminar organised by Sir Syed Movement, a social organisation. He was to address the seminar tomorrow.br br No official reason was given for the cancellation of the visit by the district administration.