The Liverpool player faces a disciplinary panel for swearing at German official Markus Merk following his side's 2-0 defeat against Brazil.

Kewell has until Tuesday to respond to the panel's charges and a verdict will be handed down before Australia's final group game against Croatia on Thursday.

"FIFA have opened disciplinary procedures against Harry Kewell," Siegler was quoted as saying by BBC Sport.

"It was reported in the referee's report that he insulted the referee several times," he added.

Merk awarded 25 free-kicks to Brazil while Australia won only nine, which may have led to Kewell's heated outburst after the match.

The procedure is extremely rare for a player who did not receive a booking while on the pitch.

The 27-year-old forward, who missed an open goal shortly after coming on as a second-half substitute, played down his altercation with the official calling it a "in the heat of the moment" outburst.

"You're frustrated, you're losing the game, every referee puts up with it," Kewell said.

"I mean, it's part and parcel of the game. He knows there's no harm meant by it."