US actress and humanitarian campaigner Angelina Jolie leaves a G8 Foreign Ministers Meeting in London in this April 11, 2013 file photo.[Photo/Agencies]

Pitt was by Jolie's side through three months of treatment that ended late in April, she said. The two became engaged last year.

"Having witnessed this decision firsthand, I find Angie's choice, as well as so many others like her, absolutely heroic," Pitt told London's Evening Standard newspaper.

"All I want is for her to have a long and healthy life, with myself and our children. This is a happy day for our family."

Jolie opted for reconstruction with implants. Breast tissue was removed during surgery and temporary fillers were inserted in their place. Nine weeks later the surgery was completed with the implants.

"On a personal note, I do not feel any less of a woman," she wrote. "I feel empowered that I made a strong choice that in no way diminishes my femininity."

The actress decided to be open about her surgery after finishing treatment to help women who might be living under the shadow of cancer.

"It is my hope that they, too, will be able to get gene tested," she said.

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