Don’t work for Ozzy and Sharon, the Writers Guild of America is warning its members.

The WGA sent a letter to its members and top talent agencies putting members on alert that they could be subject to fines if they take a writing gig on the upcoming Fox comedy-variety show hosted by the Osbournes. Osbournes skein, which is expected to air this season, is produced by FremantleMedia North America. Fremantle has been a recent target of protests by the WGA for the lack of a WGA contract for the mega-hit “American Idol.”

“Any members who perform writing services on that show do so at their own peril as they will be violating WGA Working Rule 8 and could be fined up to 100% of their compensation for that work,” the joint letter from WGA West and WGA East said.

WGA execs said the guild had been trying to negotiate a WGA contract for the Osbournes show but were recently told by a Fremantle exec that the talks were over. Fremantle, on the other hand, said in a statement that it was the WGA that broke off the talks, and then “implemented their usual mendacious strategy of feeding misleading and erroneous information to the press.”

Jeff Hermanson, WGAW’s assistant exec director, said that Fremantle sought to negotiate a contract that covered only some aspects of the writing done on the Osbournes show, arguing that the show was a hybrid reality-comedy skein. Hermanson said they were willing to bargain with Fremantle but there was “no way we were going to agree to unreasonably sub-standard terms.”

The last time the WGA sent such a warning letter to members about a specific show was about a year ago regarding the Fremantle gameshow “Temptation.” Four staffers walked off that show in protest of what they alleged were onerous working conditions and Fremantle’s resistance to negotiating a WGA contract for producers serving writer-like functions on the show.

Fremantle’s “Idol” has also been the subject of an extensive WGA protest campaign, dubbed the “American Idol Truth” tour, which crisscrossed the country this summer as “Idol” producers held regional auditions for its upcoming season. WGA maintains that producers on the show who function as scribes should be covered by WGA contract.

The joint letter also referenced the WGA’s fight with multihyphenate Tyler Perry over WGA coverage for the Perry-produced TBS sitcoms “House of Payne” and “Meet the Browns” (Daily Variety, Oct. 3), reminding members that they are not allowed to work on those shows.

“Denying Fremantle and Tyler Perry members of the Writers Guilds East and West may convince them that they will be unable to produce professional quality entertainment content and that they will see the wisdom and creative advantages of signing a WGA contract,” the letter said.