The Writers Guild of America West has told its members that they must stop working on shows for Central Prods., the production arm of Comedy Central, if there is no WGA contract in place on a particular show.

The guild, which is in the midst of negotiations with Comedy Central, disclosed the admonition to members in an email sent Monday from president Chris Keyser, VP Howard Rodman, secretary-treasurer Carl Gottlieb and exec director David Young.

Comedy Central spokesman Steve Albani said, “We’re continuing to move forward on our negotiations with the Writers Guild and are hopeful that we’ll come to an agreement soon.”

It’s not immediately clear which shows are affected by the WGA West’s order. Comedy Central stalwarts “The Daily Show With Jon Stewart” and “The Colbert Report” are covered by contracts with the WGA East.

“If you are currently writing on a Central Productions project, please contact us immediately,” the guild’s email said. “Central Productions is not signatory to the MBA, and if there is no guild contract in place specifically for the project you are working on, you are now required under Working Rule 8 to stop writing.”

The missive accused Central Prods. of hiring writers without a WGA contract in place — while telling the writers falsely that they were covered for 15 shows last year and more than two dozen projects this year.

“No other major entertainment company has treated writers and their guild so cavalierly,” the letter said.

The letter recapped the history of WGA’s ongoing battles with the network. It noted that the WGA began covering five Comedy Central shows in 2007 via individual “letters of adherence” rather than by an overall minimum basic agreement, followed by 37 agreements from 2008 to 2011 — resulting in WGA coverage of all non-animated shows on Comedy Central. Subsequently, the guild said, writers were hired on more than three dozen shows under the false pretense of coverage by the WGA.

“To protect writers from these practices, this summer the guild entered into negotiations with Central Productions to reach an overall deal that would eliminate the need for project-by-project Letters of Adherence,” the WGA letter said. “These negotiations are ongoing. We intend to take this opportunity to negotiate the best possible contract terms, including industry-standard residuals formulas. We also intend to protect against the company’s practices of hiring writers before a deal is in place and of attempting to negotiate MBA terms directly with individual writers rather than with the guild.”

As a result, the WGA West said, until an agreement with Central Prods. is concluded, WGA West members may not work on uncovered Central Prods. projects.

“It is never easy to ask a fellow member to stop working,” the letter said. “We understand all too well that such a call comes with the real possibility of personal sacrifice. We do not do it lightly. But the principle that we work, all of us, under a contract with certain basic protections that may not be undercut and that may not be renegotiated, member-by-member and case-by-case, is the cornerstone of our strength. As Central Productions’ behavior has proven once again, guild coverage cannot be a sometimes thing. And so, while we might rightly say to Central Productions shame on you, what we say instead is: no more. Without a contract there will be no work. And we must say that together — all of us, no exceptions — as a guild.”