“As hard as it will be to leave Ballymore, my teammates, the staff and all my fans and friends in Queensland, I’ve been offered a fantastic opportunity with Harlequins to experience rugby in another part of the world and this is right for me at this stage of my rugby career,” Horwill said in a statement.
“I’m completely committed to helping the Reds and Australia achieve success in this World Cup year and then I’ll turn my attention to the next chapter of my life in rugby with Harlequins.”
Horwill will join a number of England internationals, including captain Chris Robshaw, at the Twickenham-based club, but remains fully focused on his final Super Rugby season.
“We’ve got some fantastic ability across the park and that’s the big thing for me to make sure we finish my time here on the right note and we live up to our potential as a team,” Horwill told ABC’s Grandstand.
“It’s good now I can focus purely on the Reds campaign and rugby next year.
“I don’t need to worry about what my future holds and what I want to do. That was always the plan in my head to get it done before the end of this year, so we can go into next year with a pretty clear mind and clear focus on what the plan is.”
Fellow Wallabies teammate Adam Ashley-Cooper has joined Horwill in accepting an international offer, announcing a deal with French club Bordeaux following the World Cup, however Wallabies coach Michael Cheika say he is “not at all” concerned with the prospect of losing home-grown talent to overseas offers.
“We want to make sure that our environments, both in Super Rugby and in the Australian team, are so good that players don’t want to leave because they’re enjoying themselves and they’re getting what they want out of rugby,” Cheika said on Thursday.
“Everyone’s in the same boat,” Cheika added. “Even our young players because it’s not just our top players who are leaving.
“It’s on everywhere, but that’s the natural market and in any marketplace we’ve got to make ourselves an attractive option as well, and not just around money.”
The Wallabies’ 2015 World Cup campaign kicks off on September 23 against Fiji in Cardiff before games against Uruguay, England and Wales.
Photo: Bradley Kanaris/Getty Images.