A drunken young City trader who downed pints of beer and allegedly snorted lines of cocaine turned into Tarzan when he tore off his shirt and attacked a taxi driver.

Camberwell Green magistrates were told that James Browning, 26, told his victim that he had endured a "crap night" before launching the assault. The court was told that he said he became violent because "I always do when my friends get me on charlie."

Christian Wheeliker, prosecuting, told magistrate John Verdon: "That is slang for cocaine."

Browning, who denied taking cocaine on the night of 5 April, was driven by cabbie Dean Wendleken, 49, to Southwark, south London, where he got out of the taxi to withdraw money from a cashpoint for the £28.40 fare.

But the London Metal Exchange associate instead told Wendleken that he had no cash at all and had also lost his bank cards before running off. Wendleken tracked him down and challenged him. Browning replied: "I aint giving you f***all!"

Browning, who is employed by Newedge Group in Bishopsgate, then became violent, prosecutors said.

"Browning was jumping up and down like Tarzan, ripping his shirt off and spoiling for a fight," the court heard.

He headbutted Wendleken before slamming shut the door on the taxi driver's head. The 49-year-old victim was soaked in blood and needed stitches.

Police tracked down Browning from his mobile phone which he had lost in the melee. He admitted assaulting Wendleken and causing actual bodily harm. The court heard that he had burst into tears under questioning by police.

Browning was sentenced to 240 hours' community service and ordered to pay £725 in compensation.

Verdon told Browning he was lucky to escape a jail term: "This was a nasty offence. We don't often see category one actual bodily harm cases like this at the higher end of our sentencing guidelines.

"You have enrolled in counselling, you are of good character and you have made admissions to the police, which has been taken into consideration.

"You are very lucky because it passes the custody threshold."