At a news conference yesterday, Sir Elton said: "There were three people I was really impressed with and they just happened to be black, young female singers."
Sir Elton, who was a guest judge on the show earlier this month, said that singers Jennifer Hudson, La Toya London and Fantasia Barrion all had "great voices". He commented that they all seemed to be landing in the bottom three and he found it "incredibly racist".
Fellow judges Simon Cowell, singer Paula Abdul and music producer Randy Jackson also agreed that the three black divas remaining on the show blow the rest of the competition away.
However, 20m Americans voted to stick the singers in the bottom three and give Jennifer Hudson the boot. Sir Elton is one of a number of guest judges -- earlier this month 'Kill Bill' director Quentin Tarantino appeared on the show and ripped into contestants.
The Hudson result prompted the show's host Ryan Seacrest to remind voters that the series was a talent show not a popularity contest. "America, don't forget you have to vote for the talent. You can not let talent like this slip through the cracks," he said at the end of last week's show.
However, black singer Ruben Studdard won 'American Idol' last year. As in the UK version, the person with the lowest number of votes is eliminated.
The programme maker, Fox Television, has declined to comment.
Last month it was Cowell who was in trouble after he was accused of giving the finger to his fellow 'American Idol' judge Paula Abdul.
Separately, Sir Elton fronted a Rainforest Foundation benefit concert with Sting in New York last week. They were joined by Billy Joel, James Taylor and Bette Midler.
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