Canadian model Gabriel -- who has a one-month-old daughter Nahla Ariela with Halle -- is said to have proposed to the X-Men actress, and given her a ring which first belonged to his grandmother.

A source close the couple revealed: "Gabriel felt the time was right to propose. He gave her the family heirloom because he wanted to show her how much she means to him, and how she will be accepted into the Aubry family.

"The ring belonged to Gabriel's grandmother -- it was her engagement ring."

Halle was first seen wearing a diamond ring on her engagement finger at the Revlon Walk/Run for Women in Los Angeles at the weekend.

The 41-year-old actress has also been wearing a necklace bearing the letter "N" for Nahla.

Halle -- who was last seen in movie Things We Lost in the Fire -- will next appear in and produce psychological drama Frankie and Alice.