A major cast shakeup is occurring for The Real Housewives of Orange County.

Gretchen Rossi and Alexis Bellino will not be returning for Season 9, Life & Style reported.

"Gretchen and Alexis are not going to be back next season," an insider said. "Every season they look at how to shake up the cast. They needed new women and in order to do that they had to say goodbye to some of the current cast."

'The Real Housewives of Orange County' Alexis Bellino Without Makeup

According to the insider, both stars wanted to come back and are upset about Bravo's decision to not re-sign their contracts.

Gretchen and Alexis have been on the series since Season 4 and Season 5, respectively.

"Alexis doesn't really have much going on and Gretchen has reached the end of her story on the show -- she's happily engaged and starting a new life with Slade [Smiley]," the source added.

Producers have asked Tamra Barney, Vicki Gunvalson, Heather Dubrow and Lydia McLaughlin back, Radar Online reported last week, and season 9 starts filming this month.