They say politics is a rough old trade – but Boris Johnson may have taken it too far today after sending a nine-year-old stumbling to the floor in a friendly football kick-about. The London Mayor joined in a children's match to promote a new health report aiming to get more kids involved in sport. But after seeing one youngster knock the ball past him Mr Johnson stuck his leg out, tripping him up, sparking shouts of 'Referee!' from the side-lines. Scroll down for video . Boris Johnson . joined children for a kick around today after his health advisor Lord Darzi called for further bans on smoking in public places . After showing little enthusiasm for the game, Mr Johnson stuck his right foot out and tripped the boy up . Mr Johnson later issued an apology and insisted he was 'going for the ball' Mr Johnson was supposed to be promoting the health benefits of playing sport. But he instead had to issue a public apology for his behaviour on the football field, set up outside City Hall near Tower Bridge in London. Wearing his suit and moving slowly across the grass, he stuck his right foot in for the tackle and sent the youngster flying. He told Sky News: 'That was a total mistake. I apologise very much. I was going for the ball.' Mr Johnson has a history of reckless fouls on the football pitch after infamously leaving an opposition player sprawled on the floor after tacking him in a charity game – with his head. The London Mayor – who was then the MP for Henley – was taking part in a charity England-versus-Germany match in front of 15,000 people at the Madejski stadium in Reading in 2006. With eight minutes to go he accidentally passed to German No 6, Maurizio Gaudino – before attempting a rugby-style tackle to retrieve the ball. After the final whistle, Mr Johnson, gripping a can of lager, said: 'There was no malice in my actions. I was going for the ball with my head, which I understand is a legitimate move.' He added: 'To be honest, I'm a rugby player. I was always getting penalised for fouling when I played football.' The London Mayor sent one youngster stumbling to the floor after tripping him in the game outside Tower Bridge . Mr Johnson has a history of reckless fouls on the football pitch after infamously leaving an opposition player sprawled on the floor after tacking him in a charity game – with his head. The London Mayor – who was then the MP for Henley – was taking part in a charity England-versus-Germany match in front of 15,000 people at the Madejski stadium in Reading in 2006. With eight minutes to go he accidentally passed to German No 6, Maurizio Gaudino – before attempting a rugby-style tackle to retrieve the ball. After the final whistle, Mr Johnson, gripping a can of lager, said: 'There was no malice in my actions. I was going for the ball with my head, which I understand is a legitimate move.' He added: 'To be honest, I'm a rugby player. I was always getting penalised for fouling when I played football.' Mr Johnson's latest football indiscretion comes after he was forced to dismiss calls for a ban on smoking in public parks - after the Mayor's top health advisor called for the dramatic measure to be introduced. Lord Darzi said the capital should follow New York's example by banning smoking in Trafalgar Square, Parliament Square and the Royal Parks in a bid to reduce the 8,400 annual early deaths among London smokers. But Mr Johnson today said he has refused to act on the call for a ban - despite former New York Mayor Mike Bloomberg crediting the policy as having boosted life expectancy by nearly three years. Claiming there was a lack of clinical evidence in the NHS to justify a ban, he said: 'There are many other proposals in this report that I think involve less bossiness, less nannying, less finger-wagging than telling people they can't smoke in a vast open space. 'I think smoking is a scourge and people should be discouraged from smoking, but actively to ban people from doing something that is legal in a big open space is taking bossiness too far.' Boris Johnson, right, tackles German's Maurizio Gaudino during a charity match at the Madjeski stadium in Reading in 2006 . The England versus Germany charity game was organised to raise money for The British Red Cross and the Bobby Moore Fund . Dame Tessa earlier told the Standard she would act if elected to City Hall in 2016. 'If you are asking somebody of Ara Darzi's eminence and reputation to conduct an investigation like this, you have got to have a pretty good reason for not accepting it if you want to improve the health of Londoners,' she said. 'The recommendations are all grounded in evidence and have public support - 59 per cent are in favour of a ban. 'Lord Darzi has looked at the very radical proposals that Mayor Bloomberg introduced in New York. These have been tried and tested. Similar protections should be offered to Londoners. 'If I were Mayor of London, promoting the health of Londoners would be one of the key areas I would want to act on.'
London Mayor joined in a children's match to promote a new health report .
Johnson tripped nine-year-old sparking shouts of 'Referee!' from onlookers .
The prospective Tory MP has a history of reckless fouls on the football pitch .
They say politics is a rough old trade – but Boris Johnson may have taken it too far today after sending a nine-year-old stumbling to the floor in a friendly football kick-about. The London Mayor joined in a children's match to promote a new health report aiming to get more kids involved in sport. But after seeing one youngster knock the ball past him Mr Johnson stuck his leg out, tripping him up, sparking shouts of 'Referee!' from the side-lines. Scroll down for video . Boris Johnson . joined children for a kick around today after his health advisor Lord Darzi called for further bans on smoking in public places . After showing little enthusiasm for the game, Mr Johnson stuck his right foot out and tripped the boy up . Mr Johnson later issued an apology and insisted he was 'going for the ball' Mr Johnson was supposed to be promoting the health benefits of playing sport. But he instead had to issue a public apology for his behaviour on the football field, set up outside City Hall near Tower Bridge in London. Wearing his suit and moving slowly across the grass, he stuck his right foot in for the tackle and sent the youngster flying. He told Sky News: 'That was a total mistake. I apologise very much. I was going for the ball.' Mr Johnson has a history of reckless fouls on the football pitch after infamously leaving an opposition player sprawled on the floor after tacking him in a charity game – with his head. The London Mayor – who was then the MP for Henley – was taking part in a charity England-versus-Germany match in front of 15,000 people at the Madejski stadium in Reading in 2006. With eight minutes to go he accidentally passed to German No 6, Maurizio Gaudino – before attempting a rugby-style tackle to retrieve the ball. After the final whistle, Mr Johnson, gripping a can of lager, said: 'There was no malice in my actions. I was going for the ball with my head, which I understand is a legitimate move.' He added: 'To be honest, I'm a rugby player. I was always getting penalised for fouling when I played football.' The London Mayor sent one youngster stumbling to the floor after tripping him in the game outside Tower Bridge . Mr Johnson has a history of reckless fouls on the football pitch after infamously leaving an opposition player sprawled on the floor after tacking him in a charity game – with his head. The London Mayor – who was then the MP for Henley – was taking part in a charity England-versus-Germany match in front of 15,000 people at the Madejski stadium in Reading in 2006. With eight minutes to go he accidentally passed to German No 6, Maurizio Gaudino – before attempting a rugby-style tackle to retrieve the ball. After the final whistle, Mr Johnson, gripping a can of lager, said: 'There was no malice in my actions. I was going for the ball with my head, which I understand is a legitimate move.' He added: 'To be honest, I'm a rugby player. I was always getting penalised for fouling when I played football.' Mr Johnson's latest football indiscretion comes after he was forced to dismiss calls for a ban on smoking in public parks - after the Mayor's top health advisor called for the dramatic measure to be introduced. Lord Darzi said the capital should follow New York's example by banning smoking in Trafalgar Square, Parliament Square and the Royal Parks in a bid to reduce the 8,400 annual early deaths among London smokers. But Mr Johnson today said he has refused to act on the call for a ban - despite former New York Mayor Mike Bloomberg crediting the policy as having boosted life expectancy by nearly three years. Claiming there was a lack of clinical evidence in the NHS to justify a ban, he said: 'There are many other proposals in this report that I think involve less bossiness, less nannying, less finger-wagging than telling people they can't smoke in a vast open space. 'I think smoking is a scourge and people should be discouraged from smoking, but actively to ban people from doing something that is legal in a big open space is taking bossiness too far.' Boris Johnson, right, tackles German's Maurizio Gaudino during a charity match at the Madjeski stadium in Reading in 2006 . The England versus Germany charity game was organised to raise money for The British Red Cross and the Bobby Moore Fund . Dame Tessa earlier told the Standard she would act if elected to City Hall in 2016. 'If you are asking somebody of Ara Darzi's eminence and reputation to conduct an investigation like this, you have got to have a pretty good reason for not accepting it if you want to improve the health of Londoners,' she said. 'The recommendations are all grounded in evidence and have public support - 59 per cent are in favour of a ban. 'Lord Darzi has looked at the very radical proposals that Mayor Bloomberg introduced in New York. These have been tried and tested. Similar protections should be offered to Londoners. 'If I were Mayor of London, promoting the health of Londoners would be one of the key areas I would want to act on.'
a friendly football kick-about. The London Mayor joined in a children's match to promote a new tripping him up, sparking shouts of 'Referee!' has a history of reckless fouls on the football