Phillips, 30, played a key role in helping the British & Irish Lions to a first series win in 16 years on Saturday and will return to French club Bayonne where he has one remaining year on his contract.
He has 77 Wales caps to his name, as well as five with the Lions, and was instrumental in guiding the Red Dragons to Six Nations Grand Slams in 2008 and 2012 as well has helping them retain their crown last year.
And Phillips admits he will think long and hard before deciding if he wants to continue on the international stage.
“It may well be that if I want to play on at club level, I’ll have to call time on my international career in the not too distant future,” Phillips said.
“It’s something I’m going to think long and hard about and I’ve got some decisions to make in the next year.
“If [Saturday’s match] is to be the last game of international rugby that I play, then what a way to bow out.
“Added to that, Wales fought back to win the Six Nations last season. Who knows? I’m just glad it’s the end of the season now and I can enjoy it.
“I won’t be on the next Lions tour, but five caps and three wins? I’m happy with that.”