Button, who has competed in more than 300 races following 17 consecutive seasons in the sport, will not be on the grid next year.
His decision to stand down from McLaren - with Stoffel Vandoorne replacing Button next year - had been sold as a sabbatical.
And while McLaren still have an option to bring Button back into the fold in 2018, on Thursday the Briton sounded like a man who is ready to call time on his glittering career.
"I go into this weekend thinking it is going to be my last race, and I think that is the best way to be," said Button ahead of the season finale at the Yas Marina Circuit.
"At this moment in time I do not want to be racing in Formula One past this race. I think of this as my last race and hopefully everybody else does as well. I don't want to go into this race and think it's not my last, and it is.
"It is true that I have a contract for 2018 but at this moment in time I don't want to be racing in 2018."
Under his new ambassadorial role with McLaren, Button will still attend some of the grands prix next season as back-up to Vandoorne and Fernando Alonso, but his definitive plans are unclear.
He has been earmarked as a pundit, while he stressed he is keen to take part in more triathlons. A career in rallycross, once pursued by his late father John Button, is also be an option.
"The whole idea about having a contract was that in three months' time, when I've eaten myself stupid and am thinking of things to do in the future and maybe feel I need Formula One back in my life, but at this moment in time that isn't the case," Button added.
"So this is my last race and that's the way I think about it at the moment. But who knows? That could change in six months, eight months, one year."
Button began his career at Williams in 2000 before spells with Renault, BAR and then Honda. The Japanese manufacturer quit the sport at the end of 2008, leaving Button without a drive, but a consortium led by Ross Brawn took over the team at the eleventh hour and, in one of sport's most remarkable fairytales, Button claimed the world title in the following season, with Brawn winning the constructors' championship.
"Obviously that was a very memorable year in my life and in the future it is something I will tell my grandkids about," Button added.
"I came from nothing and we ended up winning the world championship. I will definitely step away from Formula One happy with what I have achieved and knowing that my life really does start now."
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