England's 5-0 Ashes whitewash was not the key reason for Andy Flower stepping down as team director.

England and Wales Cricket Board (ECB) chairman Giles Clarke revealed Flower opted to leave his post after deciding the team director should be directly involved in all three formats.

Flower handed over the coaching duties of the limited-overs teams to Ashley Giles 14 months ago, but after speaking with new ECB managing director Paul Downton in the past week it was agreed that situation that was no longer tenable as England plot a new era.

Flower, who won the Ashes three times during his five-year tenure, therefore opted to stand down.

"This was Andy's decision," Clarke said at a press conference in Melbourne.

"He felt going forward - in the new (Alastair) Cook era that the three formats should be unified under one coach.

"That was his fundamental decision.

"Once that decision had been reached then he didn't want to be coach of all three it was clear what his next decision would be."

Flower indicated a unified leadership team was needed for England to make "significant progress" in a statement released by the ECB to confirm his departure.

"In order for England cricket to make significant progress, I believe the team director - together with the respective captains - needs to be responsible across all formats...to positively influence the rebuilding process," Flower said.

"This will ensure complete clarity and continuity...and having stepped aside from the limited-overs squads 14 months ago, that is not something I am able to do.

"I do not therefore feel that starting the process would be in the best interests of all involved at what is a pivotal time for England cricket."

Last month, the day after whitewash was confirmed with a 281-run defeat in Sydney, Flower stressed his appetite for the battles ahead.

Three and a half weeks on, however, he felt unable to complete that task. Flower is instead set to take on an yet-to-be-determined role at the ECB, most likely working in player development.

Clarke did not put a timeframe on when a successor would be appointed, although Giles appears well placed after being ushered in as his understudy.

The former Warwickshire boss was praised, without commitment, by Clarke who said Downton would begin a process to find Flower's replacement.

It is a task he has time to mull over, with England not due to play a Test match until they host Sri Lanka at Lord's on June 12.

"He (Giles) is a very strong candidate," Clarke said.

"Ashley is a very valued employee of the ECB, We all have the highest regard for him both as a man and as a coach.

"There may well be other outstanding candidates that emerge it will be a matter for Paul and those he chooses to advise him on that to decide who the right person is."

Clarke backed Cook to remain as skipper of the Test and ODI teams.

Cook had revealed some self doubt about his captaincy during the 4-1 ODI series defeat in Australia, but will now meet Downton in the coming weeks to discuss the direction of the England team.

"I expect Alastair Cook to be captain of the team for the first Test next summer and for the ODIs at home," Clarke said.