The 51-year-old former team principal - who was at the helm of Red Bull Racing for 20 years - was fired by the Formula 1 team's parent company on Wednesday (09.07.25), and he spoke to staff in an emotional farewell speech.
Speaking in a video leaked to Sky Sports, he said: "Yesterday, I was informed by Red Bull that operationally I would no longer be involved with the business or the team moving forward.
"I will still remain employed by the company but, operationally, the baton will be handed over. It came as a shock to myself.
“I've had a chance to reflect over the last 12 hours and wanted to stand in front of all of you to break this news and to express my gratitude to each and every single member of the team that has given so much during the last 20-and-a-half years.
"When I arrived 20 years ago, there were a few less grey hairs. I walked into a team and did not know what to expect but I was immediately welcomed and we started to build what became a powerhouse in F1.”
Christian insisted he "fought hard" for the team, but still voiced his support to his incoming replacement Laurent Mekies.
He said: "Watching and being part of this team has been the biggest privilege of my life,” he added.
"A new CEO will be announced shortly. I trust him and give him my full support. My instruction to him is to look after all of you.
"I have fought hard, I've done my best, I've put in a big shift and it now comes to a close."
Horner has headed the team since its inception in 2005 - making him the longest-serving team boss in Formula One - and he led them to six constructors' titles and eight drivers' crowns during his tenure.
However, his career with the team was mired in controversy last year after the motorsport team launched an investigation into allegations of inappropriate behaviour by Horner towards a female colleague.
The initial investigation cleared Horner and an appeal against the findings was later dismissed.
Horner - who denied all claims of inappropriate behaviour - later told Sky Sports News: "Obviously, it's been a hugely thorough process and, of course, I was relieved with the appeal concluding and dismissing the claim.
"So, now It's very much, as it has been all season, focus on track, here at Max's [driver Max Verstappen] home race and looking forward to these last 10 races."
The announcement of Horner's departure comes on the back of a disappointing result for the team at the British Grand Prix at Silverstone last weekend as Max Verstappen landed in fifth place.
