Police were scrambled to the premises in Regent’s Park Road, in Camden, after reports that a man had hurled a glass at a woman in her 30s.
The alleged incident happened at just after 8.25pm on 25 July.
Officers interviewed the woman who claimed that the man had used racially offensive language to her before allegedly throwing the glass.
The man had left the pub prior to officers’ arrival and police have failed to identify him despite “extensive inquiries”.
He is described as white, approximately 50-years-old, 5ft 8ins tall and of stocky build.
He was wearing a dark coloured tracksuit and the people with him referred to him as Louis.
Detective Constable Sanheeta Dighe said: “I would urge ‘Louis’ to come forward and speak with us about what happened that evening. Likewise, if you know who he is, please contact us.”
Anyone with information is asked to call police via 101 quoting reference CAD 6307/25Jul. To remain anonymous call Crimestoppers on 0800 555 111.