Tommy Robinson will not be charged over an alleged assault at St Pancras railway stations last month.
The Crown Prosecution Service concluded 'there was not a realistic prospect of conviction', British Transport Police said.
It comes after the 42-year-old was arrested at Luton Airport on suspicion of grievous bodily harm in connection with an incident at St Pancras station on July 28.
The police force previously launched a probe after reports a man was assaulted at the busy London railway station.
A day later, Robinson had gone to Tenerife and was wanted for questioning after video emerged of him walking away from the scene.
