The Godolphin-owned five-year-old has struck gold at the highest level on three occasions this season, dominating his rivals in the Lockinge Stakes at Newbury and the Queen Anne at Royal Ascot before bouncing back from defeat at Goodwood to win the Prix du Moulin at Chantilly.
He was a hot favourite to claim his fifth Group One success overall in the Queen Elizabeth II Stakes at Ascot on Saturday, but with the rain-softened ground against him, he had to make do with the runner-up spot behind John Gosden's filly Persuasive.
Darley confirmed on Tuesday morning the son of Iffraaj will take up stallion duties next year, when he will command a fee of €30,000, but there is the possibility of one final hurrah at Del Mar in California on Saturday week.
Fahey said: "I've spoken to Joe (Osborne, Godolphin chief executive) who has spoken to the boss (Sheikh Mohammed). Basically, they're leaving the decision (on the Breeders' Cup) to me and I'm leaving it to the horse.
"He seems to have come out of Ascot well, but I'm going to leave it a few more days and let him tell me whether he wants to go or not."Ribchester is a best-priced 9-2 for the Breeders' Cup Mil with BetVictor. (PA)
Fahey's comments come on the back of him speaking to Racing UK's Luck On Sunday programme when he stated that he would be "more than happy" to take Ribchester to Del Mar for the November 4 date.
Reflecting on Ribchester's racing career, the trainer added: "We just feel very privileged to have had him and I'm sure he'll be a super stallion.
"Without wanting to disrespect any of the other horses we've trained, the ratings tell you he's the best we've had, so it's very easy to say that."