Bondi Beach and Kingfisher are set to be Irish trainer Aidan O'Brien's first Melbourne Cup runners for seven years with Lloyd Williams buying shares in the pair.

The leviathan Australian owner has also bought into Irish St Leger winner Order Of St George who is less likely to make the trip.

O'Brien expressed his delight at Williams, a four-time Melbourne Cup-winning owner, being involved with the trio of horses.

"Lloyd is a legend in his own lifetime," O'Brien said.

"We feel very privileged to have horses to train for him.

"The three of them are possibles for the Melbourne Cup, obviously. They have to go into quarantine with us on Tuesday and they'll possibly go in anyway.

"It's looking very possible that Bondi Beach and Kingfisher will go and we have to make a final decision on Order Of St George."

Bondi Beach was declared the winner of the English St Leger after an inquiry while Kingfisher finished second in the Ascot Gold Cup.

O'Brien hasn't had a Cup runner since 2008 but won last year's Cox Plate with Adelaide.