Drinkwater will leave Chelsea this summer after five disappointing years.
Drinkwater made just 23 appearances for Chelsea after his big-money move from Leicester City, where he won the Premier League title in the 2015/2016 season.
The 32-year-old embarked on loan spells at Aston Villa, Burnley, Kasimpasa and Reading in a bid to recapture his old form but his contract expires next month and will not be renewed.
Drinkwater won the FA Cup with the Blues in the 2017/2018 season but admits his time at the club has not gone according to plan.
"My time at Chelsea has come to an end… actually feels really strange writing this," the three-time former England international wrote on Instagram.
"Me, the club and fans are hugely disappointed with the outcome there is no doubt about that.
"Injuries, how I have been treated, mistakes I have made, issues of the pitch, lack of game time… the list of excuses could be endless but I would not and can not change what’s happened.
"I’m going to look at positives over the past five years, I have played with great players, coached by awesome managers, worked with some brilliant staff, met some fantastic people, lived in some beautiful places, travelled the world and won some more silverware.
"Footballs a fantastic sport but this for both parties was a business move gone wrong, it’s as black and white as that.
"To the Chelsea fans I apologise for how this has turned out I would have loved for u to see me at my best in that shirt doing what I love."
