London Mayor Boris Johnson tackles 10yo boy

London Mayor Boris Johnson has apologised after he tackled a 10-year-old Japanese boy during a street rugby tournament in Tokyo.

Mayor of London Boris Johnson knocks over 10-year-old Toki Sekiguchi. Source: AAP

A 10-year-old Japanese boy was left bruised but otherwise unijured after London Mayor Boris Johnson tackled him to the ground.

Mr Johnson was participating in a street rugby tournament with school children and adults from Nihonbashi, Yaesu & Kyobashi Community Associations in Tokyo on Thursday

He was running with the ball during the game of touch footy, and as Toki Sekiguchi ran towards him Mr Johnson dipped his shoulder and tackled the boy, knocking both of them to the ground.

Mayor of London Boris Johnson knocks over 10-year-old Toki Sekiguchi. Source: AAP

The 10-year-old told Mr Johnson he "felt a little pain", but was ok and the mayor later presented him with a 2015 rugby ball.