The man then calmly walked away from the woman towards platform four and onto a train.
Luckily the victim was not left with any visible injuries, but this was a shocking and unprovoked assault.
We do not tolerate violence like this anywhere on the rail network and I'd urge anyone who recognises the man pictured, or who may have witnessed what took place, to come forward and assist officers in this investigation.
More top news
Transport for London is being forced to pull down Germanwings tube adverts with the words "get ready to be surprised" after the fatal crash
Two huge boring machines are entering the final stage of their 26 mile journey underneath London's streets
A new social enterprise cafe is looking for £50,000 to make their dream of serving healthy fried chicken to Tottenham's kids a reality