French star Cirrus Des Aigles has been retired by trainer Corine Barande-Barbe because of a ligament problem in a leg.

Although the 10-year-old gelding is sound, Barande-Barbe says putting the horse under maximum pressure in a race is not worth the risk.

"He has been in great condition and very well, but I found that in his work for racing he was holding himself back a little so we checked his legs," Barande-Barbe told Press Association Sport.

"We couldn't see anything so we took X-rays and found a little calcification in a ligament that could be dangerous. In a race, it could break.

"We decided with the owner not to take such a risk and put the horse in danger, so we have decided to retire him while he is sound and happy."

Cirrus Des Aigles won seven Group Ones races earning his connections more than STG6.1 million ($A11.53 million) prize money.

His constitution and appetite for racing was such that he competed not only in his native France, but also Britain, Ireland, Japan, Dubai and Hong Kong.

As a gelding he was prevented from running in the Prix de l'Arc de Triomphe, but landed the Champion Stakes at Ascot in 2011 and got within two lengths of the mighty Frankel the following year.

He also won the Dubai Sheema Classic in 2012 and the Coronation Cup in 2014, and his three victories in the Prix Ganay included a triumph over dual Arc winner Treve.

Barande-Barbe said Cirrus Des Aigles would wind down over the next two months and his jockey Christophe Soumillon was likely to take him after that.

"He will do something with Christophe Soumillon when he retires," she said. "He wants to be a part of the horse's retirement."