The ECB decided to end the 33-year-old’s England career despite the South African-born batsman scoring 8,181 Test runs, 4,440 ODI runs and 1,1176 T20 runs.
It is frustrating for me because I have not totally been able to tell my side of the story
Pietersen’s controversial exit came off the back of a miserable tour of Australia with rumblings of dressing disharmony.
Cook was part of a three-man panel that informed the Surrey star of his axeing, and the England captain defended the decision.
“Of course you have to think back and ask if it was the right decision given all that was going on. But in my mind I know it is the right decision. It was a brave call and people have been talking as if it just happened overnight,” Cook told BBC Sport.
“The last thing we wanted to do was make Kevin a scapegoat for what happened in Australia. That is not what it was about at all. But at a time you have to say this is what we want going forward and that was the decision we made.
“For people to say it was a decision made on a toss of a coin is wrong and I think very disrespectful to those who made the decision because a lot of effort in the first place went into getting him back in the side in 2012. A lot of effort and thought went into making the decision now.”
Cook and the ECB have shed little light on the reasons behind Pietersen’s dismissal, and the England captain admitted he was frustrated at being unable to explain the contentious decision.
“I know things will become clearer in a little bit of time,” Cook added.
“I know it is frustrating. It is frustrating for me because I have not totally been able to tell my side of the story. People just have to be a little bit patient.”
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BIOGRAPHY: Marcus Rashford