Actor and rapper was angry at attempt to kiss him.
Will Smith slapped a reporter at the premiere of his new movie in Russia.
Ukrainian television joker Vitalii Sediuk made a play for Will as he went to interview him for his TV show.
However Vitalii's tries at locking lips with the screen star failed when the 'Summertime' rapper managed to make several turns with his head at the same time as being gripped in a hug.
An angry Will told the prankster: ''Hey man, what the hell is your problem?''
After slapping him and moving on down the line of press members, he later laughed the incident off.
He told another uninvolved reporter: ''He tried to kiss me on the mouth. He's lucky I didn't try to sucker punch him. ... Sorry, I said that on camera.''
This isn't the first time the clown has angered a celebrity.
He is best known for playing a prank on Madonna by presenting the singer with Hydrangeas, her most loathed flower.
The 'MDMA' star was later caught on camera after the incident at Venice Film Festival last year, telling her assistant that she hated them.