Unsold Warhol portraits up for auction

Andy Warhol's portraits of Elvis Presley and Marlon Brando are expected to go under the hammer at auction for a combined $US130 million ($A140.65 million).

The Triple Elvis (Ferus Type), created with ink and silver paint in 1963, depicts the rock icon as a cowboy, shooting from the hip, while the Four Marlons silkscreen piece features a quartet of prints of the acting legend on a motorcycle, wearing biker gear.

The portraits, which have never come up for auction before, are both over two metres high and were acquired by bosses at German casino firm WestSpiel in the late 1970s.

The artworks will be sold separately at Christie's auction house in New York on November 12.