Oprah Winfrey and Rosie O'Donnell are reportedly not speaking to each other.

The chat show hosts have apparently fallen out over Oprah's decision to drop Rosie's talk show from her OWN network because of poor ratings. The problems are believed to have started when Oprah first called the comedienne to deliver the news.

"It was a very strained conversation, obviously. Oprah wanted to handle the announcement of the cancellation in a professional and dignified manner. Rosie thanked Oprah for the opportunity and ended the conversation very abruptly," a source said.

Rosie, 49 - who is engaged to headhunter Michelle Rounds - is said to have ignored her friend's subsequent pleas to call her so they could work on the press release together.

"Rosie didn't like the initial language of the press release because she felt that it placed sole responsibility of the failure of the show on her. Oprah didn't need to get Rosie's input or approval for the press release, but she was trying to be gracious. [OWN] got a phone call from Rosie's camp, explaining what needed to be included into the press release. This is Oprah's network, and she has the final say. Oprah told her staff to have Rosie call her directly to address her concerns. Rosie never called Oprah. She was having her people do all the dirty work for her," the insider said.