Katie Holmes recently was overheard saying "I love you" to beau Jamie Foxx, an insider exclusively tells Us Weekly Credit: Gilbert Carrasquillo/FilmMagic; Valerie Macon/AFP/Getty Images

Sly with her Foxx!

Katie Holmes and Jamie Foxx aren't just holding hands behind closed doors. An insider exclusively reveals to Us Weekly that the couple have reached the "I love you" level of their relationship.

The Mania Days actress, in particular, dropped the L-word during a phone call with Foxx, 47, after landing at L.A.'s LAX Airport recently.

"She said she loved him," the source tells Us. "She always gushes about how amazing he is and the joy he brings into the world."

Us exclusively revealed back in March that Holmes, 36, and the Annie actor never stopped seeing each other since first hooking up in October 2013. "Jamie is someone she can trust and have fun with," an insider told Us at the time.

As for what Foxx may have told friends when Holmes rang from LAX? As a source previously noted, he's quick to call her "my girl" to pals. As in, "My girl is calling."

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