The man is accused of making anti-Semitic comments as he abused his male victim.
Police admitted that, despite extensive enquiries, no arrests have been made and they have been unable to identify the man in the CCTV footage,
Detective Chief Inspector Michael Dougall, a crime manager at the Metropolitan Police said: “The Met takes hate crime extremely seriously.
“Incidents of this nature against any individual or group will not be tolerated and have no place in our city. The victim of this abuse was simply on his way home on the bus.
“No one should have to go through that experience and we will act quickly and robustly in response to all reported crimes of this nature.
“Someone must recognise this man so please do the right thing and contact police."
The shocking incident came to light after footage of it was shared on social media.
Siwan Hayward, director of compliance, policing operations and security at Transport for London added: “We are appalled by the shocking incidents.
“All our customers have the right to travel without fear of abuse or intimidation, and hate crime has absolutely no place on our network. We stand against hate crime and are looking into these incidents urgently with the police.
“We urge anyone who experiences or witnesses hate crime to report it to the police immediately. It's important that people tell us so we can stop it from happening again.”
Anybody with any information about this man should call 101 quoting CAD 1440/4July or to remain anonymous call Crimestoppers on 0800 555 111.
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