Don Arnold / WireImage 1 / 12
Don Arnold / WireImage 1 / 12

In a time not too long ago, Giuliana Rancic and Kelly Osbourne appeared to be as thick as thieves on television. Now, it seems, there is nothing but radio silence between them.

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Just like Kelly has insinuated in tweets, Giuliana revealed that she doesn't have many warm, fuzzy feelings about her former "Fashion Police" costar either. The bad blood seemed to start after the death of the late Joan Rivers, but really boiled over when Giuliana made a controversial joke about young actress Zendaya, one of Kelly's friends.

"I haven't talked to [Kelly or Kathy Griffin] since the incident," the E! News host said in a "HuffPost Live" interview on April 7. "There's nothing good that can come of trying to speak for them, [or guess] what they meant by their comments."

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Giuliana is used to hearing negative comments about herself — many people have lambasted her by saying she's too thin — but on April 7 she was able to sort of fire back as she released her book "Going Off Script."

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Even the simple release of the book apparently didn't sit well with Kelly, who ominously tweeted, "Liars always get caught."

"The tweet is definitely about Giuliana," a source told Us Weekly. "They're totally feuding."

Remember those days when Kelly called Giuliana a "strong woman?" That day seems like a world away now.