Hundreds of protesters have gathered outside the Oxford Union where Prof Kathleen Stock is speaking.
Pictures show her arriving at the 200-year-old debating society.
Members of the university's LGBTQ+ Society staged a peaceful protest outside the building where queues to attend the talk stretched back to Bonn Square.
READ MORE: Live updates as Kathleen Stock speaks in Oxford
Police are present and a counter protest is taking place.
Inside the union, Prof Stock was interrupted by three protesters who were removed by police.
Professor Stock (centre) quit her job as a lecturer at the University of Sussex after being targeted by activists over her views on gender identity.
Critics say her views are transphobic and student groups asked for her invitation to the Union to be rescinded.
This morning Prime Minister Rishi Sunak weighed into the debate, saying "We mustn't allow a small but vocal few to shut down discussion."
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