The Manchester City midfielder was assessed by a specialist on Friday and his Eastlands boss Roberto Mancini confirmed he was facing a lengthy spell on the sidelines.
'I am very sorry for him because Gareth is a fantastic player,' said Mancini. 'But I hope he is called up for the World Cup. (He will be out for) three to four weeks.'
Crocked: Barry is helped off
It is terrible news for Fabio Capello, who next week names hisprovisional 30-man squad for the finals. The Italian has previouslymade it clear he would not risk unfit players, but there are fewoptions to replace Barry.
With Owen Hargreaves only just returning from a 19-month injury absence, Barry was seen as Capello's only specialist holding midfielder. That leaves the Italian turning to players like Michael Carrick, Scott Parker or Tom Huddlestone, or forcing Steven Gerrard into a more defensive role.
It is unlikely he will gamble on Hargreaves, as it may be too soon for the Manchester United midfielder.
However, Tottenham captain Ledley King has secured a place in England's provisional squad and will join Capello and his staff at their Austrian pre-tournament training camp.
Capello names his 30-man party for Austria on Tuesday they then leave on May 17. Defender King impressed Capello so much in the 1-0 win against City on Wednesday that he will be included in the party which will be reduced to 23 ahead of departure to Johannesburg on June 2.
On the plane: King is in Capello's final 23-man squad for South Africa
King's chronic knee condition is a worry but England's boss was hugely encouraged by the fact that he performed so well against City four days after playing a part in a 1-0 win over Bolton. King has 19 caps he was named in the squad 13 months ago for the games against Slovakia and Ukraine before withdrawing due to injury but he could add to that with friendlies against Mexico and Japan.
Capello must then decide if he can take a player whose condition limits how often he can play and train, in view of the fact he also has serious fitness concerns over Rio Ferdinand, Joleon Lescott and Wes Brown.
The manager may make one last attempt to tempt Liverpool's Jamie Carragher out of international retirement.
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