Independent thinking and free expression in Indian universities "are now under threat", former Prime Minister Manmohan Singh today alleged, targeting the Centre.

The Congress leader said the recent attempts to interfere with free expression of the student community in Hyderabad Central University and JNU were of particular concern and termed suppression of peaceful dissent as "inimical to learning" and 'undemocratic'.

"Regrettably, independent thinking and free expression in Indian universities are now under threat. Attempts to suppress peaceful dissent are not only inimical to learning but also undemocratic," 84-year-old Singh said while speaking at the bicentenary celebration of Presidency University.

"True nationalism is found where students, citizens, are encouraged to think and speak freely where dissents are encouraged and not suppressed. It is only by constructive engagements ..we can truly build a stronger, more cohesive and sustaining democracy in our country," Singh said and also made a veiled reference to Hyderabad University student Rohit Vemula suicide issue.

The former Prime Minister said that political interference in universities and in appointments in academic institutions was highly 'short-sighted'. "We must make very effort to protect the autonomy of our university and to foster the right of our students to express ideas," he said.

Singh said, "We are witnessing around the world a rise of nationalist tendencies, populism and hatred against backward classes and minorities in disregarding reason and rationality .....but these tendencies could be extremely destructive.

He emphasised, "We must protect India from this trend and universities have a vital role in this regard."

Singh, who wanted to be a teacher but got into politics 'by accident', said, "I believe that every university must give the freedom to pursue knowledge even where the knowledge may be at odds with established intellectual and social traditions. We must guard this freedom very zealously."