Kentucky Derby winner Animal Kingdom and two-time Breeders' Cup Ladies' Classic champion Royal Delta lead a full field of 13 horses in Saturday's $US10 million Dubai World Cup.

The pair and Dullahan represent one of the strongest American entries ever in the world's richest horse race.

Royal Delta trainer Bill Mott won the inaugural Dubai World Cup in 1996 with Cigar, but an American horse has not won the race since the track shifted in 2010 from dirt to tapeta surface.

Animal Kingdom, due to stand at Arrowfield Stud in Australia later this year, drew the 12 gate while Royal Delta - bidding to become the first filly to win the race - leaves from eight and Dullahan goes from barrier three.

Barry Irwin, founder of Team Valor which co-owns Animal Kingdom, said he was glad with the outside draw, noting his horse won the 2011 Kentucky Derby from 16 in the 20-horse field.

"I don't think it's that big of a deal," Irwin said. "He's not going to be in front anyway. He will be a mid-pack horse. We just didn't want to be inside."

Mott, who brought Royal Delta to Dubai last year only to see her finish ninth, said she was "a little banged up" last year but appears to be doing much better this year.

"Hope she breaks well and has a clean trip," Mott said of his starting post. "We are just hoping for a better trip, a smooth trip. That is all we can ask for."

Jerry Crawford, managing partner of Donegal Racing which owns Dullahan, said he, too, could live with the three gate saying it means less work for his horse which finished third at last year's Kentucky Derby and beat Game On Dude in the Pacific Classic.

The early favourite is Hunter's Light, which drew four. If he won, it would be the second straight year that the champion horse came from the stables of Dubai ruler Sheikh Mohammed.