Serena Williams has withdrawn from the US team for next weekend's Fed Cup final against Italy, the United States Tennis Association have announced.

The world number two, who is unbeaten in the Fed Cup but has not represented her country since 2007, will be replaced by Vania King for the clash against Italy in Reggio Calabria.

No reason was given for Williams' withdrawal in a short statement on www.usta.com, although the 28-year-old described herself as "wiped out" after reaching the final of the Sony Ericsson Championships in Doha.

Williams' sister Venus, who she will face on Sunday, is also missing from the US team, with much now resting on teenage sensation Melanie Oudin.

Alexa Glatch, King and doubles specialist Liezel Huber complete the line-up while Italy will be represented by Flavia Pennetta, Francesca Schiavone, Roberta Vinci and Sara Errani.