Barry had previously been doubtful for the tournament, but Capello is hopeful that his midfield anchorman will be fit and ready to play a major role in England’s World Cup campaign.
"The tests and scans two days ago say that his ankle is doing well, much better than what we had thought," the Italian said.
"Most importantly, it looks as if the recovery times will be much shorter. We'll wait until the end of this week, then we'll decide if Barry will or won't play in the World Cup, but we are very hopeful."
Whilst Barry is unlikely to feature in England’s opening fixture against the USA on June 12, a starting berth against Algeria six days later looks to be in sight.
Capello views the Manchester City midfielder as imperative to his plans, with Barry his first choice holding midfielder to allow the likes of Steven Gerrard and Frank Lampard greater license to roam forward.
The Italian also leaped to the defence of Wayne Rooney, and insisted that the striker will be travelling to the World Cup at maximum fitness this time around.
"Yes, Rooney has not scored lately, but all he does in training gives me the maximum comfort, because he has recovered 100 percent. I've always told him to play more centrally, he has all the qualities of a top goalscorer.
"Before he always helped all his team‑mates, running right and left and everywhere, and in so doing he was spending a lot of energy. Now that he keeps more in front of goal he's fresher and sharper, so he scores more [for Manchester United]."
By Joe Brewin
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