England captain Alastair Cook says he’s “frustrated” at his inability to reveal the reasons behind Kevin Pietersen’s international exile, although promises all will become clear “soon”.

Despite being England’s all-time leading run scorer across all formats, South Africa-born Pietersen was axed by the England and Wales Cricket Board in February following the team’s 5-0 Ashes thrashing in Australia.

But precisely why he was sent into international exile, with seemingly no hope of return, remains a mystery and Cook was unable to shed any fresh light on Tuesday.

“I can’t actually answer that question, totally, at this precise moment in time which is incredibly frustrating for me,” Cook told Sky Sports News at county side Essex’s media day.

“Everyone will say I’m sitting on the fence, but there are a number of reasons which will become clearer soon.

“You have to respect the decision and the position I am in at this precise moment in time,” the left-handed opening batsman added.

Initially the ECB would would only cite the need for a new “team ethic and philosophy” as the reason behind the axing of the 33-year-old Pietersen, England’s leading run-scorer in the Ashes.

But, following fierce criticism from the likes of former captain Michael Vaughan regarding such wording and that management ought to be able to handle ‘maverick’ players, the board clarified its position with another February statement saying the team had to be rebuilt and that to do that “we must invest in our captain Alastair Cook … with everyone pulling in the same direction and able to trust each other”.

The ECB added: “It is for those reasons that we have decided to move on without Kevin Pietersen.”

But that statement still left unanswered the question of what precisely Pietersen had done in Australia to deserve such drastic treatment, with some in the England hierarchy saying confidentiality reasons prevented them from revealing precise details.