Ahead of Wednesday night's friendly against Hungary at Wembley, Capello told ITV Sport the Los Angeles Galaxy midfielder is "probably a bit too old" to play for England again.
"Thank you, David," added Capello who used the former Manchester United and Real Madrid player as part of his backroom staff at the recent World Cup in South Africa.
The 35-year-old Beckham, England's most capped outfield player (115) and second most capped of all time behind goalkeeper Peter Shilton, made his debut against Moldova in September 1996.
His final international appearance was against Belarus at Wembley last October. He scored 17 goals for England.
Beckham, who missed the World Cup campaign in South Africa through injury, has not played any soccer since rupturing his Achilles tendon while on loan at AC Milan in March.
He has always said he would never retire from international soccer.
Speaking to reporters in Los Angeles after a training session on Wednesday, Beckham said he has set himself a mid-September return from injury.
"The doctor said October 1 but I hope it can be a few weeks before that," he said.
"I'll know personally when I'm right. It's my knowing if I'm right or not."
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