TV industry insiders have said the characters of Jenny 'Little J' Humphrey and Vanessa Abrams will not be returning for the upcoming fifth series of the show as it continues to chronicle the lives and loves of New York City's most beautiful, rich and infamous university students.

Taylor Momsen, who plays social climbing Humphrey, and Jessica Szohr's role of bohemian hipster Abrams, have been culled to guest starring roles for the show's next instalment.

The core five cast members of the top rating Foxtel show including Blake Lively (Serena), Leighton Meester (Blair), Penn Badgley (Dan), Ed Westwick (Chuck) and Chace Crawford (Nate) have all signed on for another season.

Serena's hell-raising cousin Charlie, played by Kaylee DeFer, has been written into the scripts and given a regular role.

The departures of Momsen and Szohr would hardly come as a surprise to Gossip Girl fans with both only starring in a handful of episodes over the past year.

Momsen, 18, will now focus full time on her music career as the front woman of her band The Pretty Reckless.

Szohr, who has been in an on-again/off-again relationship with co-star Ed Westwick since 2008, now plans to focus on her film career. She has three films in production and has just finished filming I Don't Know How She Does It with Sarah Jessica Parker, Greg Kinnear and Pierce Brosnan.

Vanessa will leave the show by announcing her plans to study abroad, while it is still not known how Jenny's character will depart.

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