The Germany international has gone on to enjoy success in a variety of competitions for Los Blancos, lifting a Liga title in 2017 and winning three consecutive Champions Leagues in 2016, 2017 and 2018 among other accolades.
The midfielder has become widely recognised as one of the world’s finest in his position, and was awarded German Footballer of the Year by kicker in 2018.
"For me, it was already clear at the time of the transfer that Bayern made a mistake with my sale," he said.
"It's true that [Bayern president] Uli Hoeness has made it public of late - and it's a testament to his greatness that he addresses it that way.
"If that was one of the reasons Pep [Guardiola] left Munich, he has to answer that, but I cannot confirm that he did not like my sale."
Kroos won his first Champions League in Bayern colours in 2013 as they defeated Borussia Dortmund 2-1 in the final at Wembley Stadium, but the Bavarian club have failed in their pursuit since then – only managing to reach the semi-final.
Hoeness recently admitted that the decision to sell the midfielder was "maybe the wrong one", saying: "An association sometimes has to make hard decisions, and that was a tough one."
The Real Madrid man extended his contract with the Liga club in May, committing himself to the 33-time Spanish champions until 2023.
He admitted that he is not sure where his career will take him once that deal expires in four years time, although he did rule out the possibility of a move to certain locations.
"I deliberately chose the end of the term in 2023," he added.
"Thirty-three could be a good age to retire, but then I also have the opportunity to decide whether or not to do something else.