Horner praised Mercedes for its development of powertrains in F1 and believes the signing of one of its top engineers will stand Red Bull in good stead for the future.
"Mercedes has done such a wonderful job, not just the six or seven years with the Hybrid era but before that with the V8," Horner told Sky Sports.
"Of course, you do your due diligence and look around at what the talent is. We have so much of that based in the UK.
"Ben's name absolutely came to the fore and he was an obvious candidate for us. I was delighted when he agreed to join the team for this exciting new chapter in Red Bull's history in Formula 1."
Former Mercedes High Performance Powertrains managing director Andy Cowell has been linked with a role at Red Bull since it was announced the team would take on its own engine programme in light of Honda's withdrawal from the sport at the end of the current season.
In response to the rumour, Horner added: "Andy is a tremendously talented engineer and everything he has achieved in Formula 1 speaks for itself.
"Andy is keen to pursue other activities and ventures so that is his priority in this point in time. We are attracting some great talent and looking forward to making some announcements in due course as we build this venture."
GPFans is a multi-platform, multi-language brand dedicated to Formula One coverage. We bring you all the ins and outs of the sport, 24/7, everything from up-to-the-minute news and features to the latest viral stories and clips.
We believe that a new generation of exciting, outspoken drivers will make F1 more popular than ever before, and we want to give our users access to as much of their heroes as possible, on and off the track. From Lewis Hamilton to Max Verstappen, Daniel Ricciardo to Sebastian Vettel, we provide in-depth analysis of every every Grand Prix in the season, from Australia to Abu Dhabi.
With Formula One under the new ownership of Liberty Media, how the sport is being covered is evolving, and GPFans will look to be at the heart of this progression into new media, as one of the fastest-growing sites covering the king of motorsports.