London: Australia batsman David Warner on Thursday apologised to Joe Root after punching the England batsman in a Birmingham bar during the ongoing Champions Trophy. "I am here today to put my hand up and apologise to Joe. I've let my team-mates, family and everyone down," the 26-year-old told a news conference.Warner said he had exchanged text messages with Root and that his apology had been accepted. Earlier Thursday, the controversial Australian batsman had been fined Aus$11,500 (Â£7,000, $11,000) and suspended until the start of the Ashes by Cricket Australia. He will miss the rest of title-holders Australia's involvement in the Champions Trophy, starting with their final group game against Sri Lanka at London's Oval ground on Monday -- a match they must win to have a chance of reaching the semi-finals -- and their two warm-up matches ahead of the Ashes.However, he will be available for the first Ashes Test against England at Trent Bridge, Nottingham, which starts on July 10. Warner said he was determined to play a role in the Ashes despite his second brush with the authorities in the space of a month. Three weeks ago, he was fined Aus$5,750 over an expletive-ridden Twitter tirade at two Australian journalists."It's up to me to be accountable for my actions, which I am, and try not to be aggressive like I did," added Warner at his London news conference on Thursday. "I've just got to move on and do everything I can to get picked for the first Test."We're not here to speculate about what happened beforehand. I definitely remember the night. It started out with a few drinks in the bar and as a team we went to the Walkabout (bar)." Australia captain Michael Clarke said that Warner must learn to behave if he is ever to realise his potential as a future skipper himself."I think David (Warner) knows how I feel about the culture of this Australian team and how important I feel the standards are in this Australian team," said Clarke. "I respect the fact David has put his hand up and wants to move forward, has apologised to Joe and acknowledged he has made a big mistake. He does deserve credit for putting his hand up."Although the punishment for David is quite harsh that's the reality when you play for the Australian cricket team. This is not an IPL team, this is not state cricket, it's not county cricket, when you play for Australia there are standards you have to uphold." Warner, who admitted he was lucky to still be involved on the tour, was dropped for Wednesday's no-result match against New Zealand, although he appeared as 12th man.