The hosts, having won the recent Ashes series with an emphatic 5-0 whitewash, comfortably beat England yet again with a seven-wicket victory in Sydney.
Cook has captained England’s one-day team since May 2011, yet may now step down to focus on leading the Test side, a job he has held for nearly two years.
“I think I’m going to have to make a decision on that after you take stock of the next two games,” Cook said. “We’ll sit down and talk over a lot of things. I think there will be some changes.”
Along with team director Andy Flower and managing director Paul Downton, Cook will review the disastrous tour of Australia when they return to England next month.
A key talking point will be the future of Kevin Pietersen, who has endured a strained relationship with Flower and may be dropped from England’s plans if Cook decides against standing by the 33-year-old maverick batsman.
Despite the one-day series defeat, Cook insists he will fight to win the remaining two matches in a bid to regain some pride. The fourth ODI takes place this Friday in Perth.