UPDATE 25/08/2017: Samsung confirmed to CNBC that the company is working on its own AI speaker. Head of Samsung's mobile division DJ Koh said that the company was working on it and an official announcement would be happening. While Koh didn't go into details, he said it was all part of Samsung's ambition to "provide a fruitful user experience at home".
Bixby, Samsung's own virtual assistant has also just gone live globally but is currently only available in English at the moment (besides, of course, Korean). If you haven't seen it yet then just manually check for updates which will be happening...so long as you set your language to English, of course.