Caitlyn Jenner's relationship with her biggest Kardashian ally may be crumbling.

Kim Kardashian was one of the first people Caitlyn told about her transition and has been one of her most vocal cheerleaders, but the reality star admitted to Ellen DeGeneres that their relationship has hit a bit of a rough patch. The issue: Caitlyn's new book, which both Kim and Kris Jenner say is full of lies about the family.

"My heart breaks for my mom. You know, because I feel like she's been through so much," said Kardashian during interview on "The Ellen DeGeneres Show" Thursday.

"She's promoting this book and she's saying all these things and I just don't think it's necessary. And I just feel like it's unfair, things aren't truthful."

When DeGeneres asked if Caitlyn was being honest, Kim replied, "No, not with certain things about my mom."

"I mean, I feel like it's taken her a really long time to be honest with herself, so I don't expect her to be honest you know, about my mom now, but it's just so hurtful," she continued. "I wish her all the success in the world, but not at our expense."

Kardashian hasn't spoken with Caitlyn "in a couple of weeks" and though she'll "always love her," she doesn't "respect the character that she's showing now."

"I'll still always have a major love for her, for who she was in my life. I'm really sentimental; I think my mom's that way," she added. "It's still Kendall and Kylie's dad, so I want to be respectful, but I just feel like there's no need for a book. You know, tell your story but just don't bash other people, you know. I just think like it's not tasteful."

DeGeneres also asked if anyone in the family has a relationship with Cait right now.

"Kendall and Kylie, that's their dad," said Kim, "I think my mom's been so respectful for so long and always wanting Caitlyn around and always wanting [them to] have a great relationship with Caitlyn, but I think you know, for the Kardashians, which she doesn't like to say that word or she said that in her book. On Diane Sawyer she purposely never said our name."

Caitlyn admitted her relationships are tough right now with the Kardashian family, especially with Kris and Khloe.

"[Khloe] doesn't want to talk to me either. She hasn't talked to me in like 2 years," Jenner told Andy Cohen Wednesday during Sirius XM townhall. "That's sad. I was very very close to Khloe. I met Khloe when she was 5 years old. Of course it hurts. She was on Howard Stern, called me a liar, that pissed me off too. If I didn't tell her anything, first of all, she never asked. Kim asked."

photos Getty Caitlyn Jenner's Most Glam Looks

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