South Africa were expecting Pienaar to leave Everton on Sunday

Everton had wanted Pienaar to play in the Carling Cup semi-final against Chelsea on Tuesday before taking part in the African Cup of Nations.

"There's a distinct grey area on this ruling," Everton secretary David Harrison told the club's website.

"We're disappointed this has only been made clear at this late stage."

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Everton had argued they did not need to release Pienaar until after Tuesday's first-leg semi-final tie as South Africa's first game in the tournament against Angola was not until 23 January.

But Fifa backed South Africa's stance that the 14-day rule for international players related to the tournament's opening game on 20 January between hosts Ghana and Guinea.

Everton had hoped South Africa might adopt Nigeria's more flexible approach.

Nigeria have given Everton permission to keep Aiyegbeni Yakubu and Joseph Yobo for the Stamford Bridge match while Nigeria midfielder John Obi Mikel should also play for Chelsea.

Barring injury, Yakubu and Yobo, will join their country's training camp in Malaga following Tuesday's game.

Pienaar trained with Everton on Monday but by mid-afternoon, South Africa had formally asked Fifa to intervene to end the confusion.

Almost every club in the Premier League will be hit by the African exodus with around 40 England-based players taking part in the tournament.