Duffy revisited his most famous role as Bobby Ewing when the legendary sex-and-scandal drama was resurrected in 2012, but it was cancelled last year (14) after three seasons.

Despite an online campaign from fans to save the beloved series, Duffy has now accepted it will never return as ABC bosses are preparing to launch new primetime soap opera Blood and Oil, which features Don Johnson as the head of a Ewing-style clan.

Duffy tells Periscope.tv, "Dallas I think is finally and ultimately laid to rest. I think the indication of that is, oddly enough, there's a new show and I believe it's on ABC and it's called Blood and Oil, and when Dallas was cancelled and ABC picked up that show... they decided there needs to be a Dallas-type show on air and there can really be only one of them so they are re-tooling Blood and Oil to be exactly like Dallas used to be, and I think that's an indication that nobody will resurrect Dallas again. Dallas is gone."

Blood and Oil is set to launch in the U.S. next month (Sep15).