SAG has agreed to patch up its relationship with AFTRA and conduct joint negotiations for the commercials contract seven months after AFTRA angrily split with its rival on primetime contract talks.

The two performers unions have also agreed to “non-disparagement” language, along with the imposition of fines for violations, in order to end the bickering that’s pervaded their relations for many years. Earlier this year, SAG national board member Justine Bateman referred to AFTRA as a “scumbag union” in a widely distributed Internet posting.

SAG said Monday that terms of the pact — signed at the guild’s national board meeting over the weekend — are confidential, but AFTRA treasurer Matt Kimbrough disclosed that the rules cover elected officials and committee members commenting in private or public on any inter-union issue. He also said each union is required to post a bond of more than $2 million in reserve to serve as a pool to mete out fines against any offenders.

“It is intentionally draconian, essentially giving the two unions a collective ‘timeout’ and resetting the standard of conduct at a very high bar,” Kimbrough said in a posting on the sagwatch.net site. “The AFL-CIO will be the arbiter of all claims and it intends on being proactive in this enforcement.”

Kimbrough said AFTRA was advised to “scrub” all critical commentaries on the Internet about SAG and asked the Sagwatch site take down his postings about “SAG Lies.”

AFTRA’s national board had approved the pact Oct. 4 after the AFL-CIO helped hammer out details via a pair of meetings between AFTRA national exec director Kim Roberts Hedgpeth and president Roberta Reardon with SAG national exec director Doug Allen and prexy Alan Rosenberg.

The resumption of a formal bargaining relationship between SAG and AFTRA was not a surprise, since both unions announced last month a series of joint membership meetings to prep for the commercial talks. Those meetings have been set in order for members to hear the results of a Booz Allen Hamilton study, commissioned by the unions and the ad industry, about the changing revenue models in the ad biz due to the impact of new media.

Additionally, SAG and AFTRA announced in late August that they had agreed to a six-month extension of their commercials contract until March 31. No date’s been set for negotiations and it’s conceivable SAG could ask for another extension, since it still hasn’t resolved the stalemate over its feature-primetime deal.

SAG announced Sunday it would ask for a federal mediator in order to jumpstart the stalled feature-primetime talks, rather than sending out a strike authorization to SAG members. The Alliance of Motion Picture & Television Producers hasn’t yet indicated if it will support mediation.

Juan Carlos Gonzalez, the same mediator who participated in the WGA-AMPTP negotiations a year ago, contacted the AMPTP on Monday.

The decision to bargain jointly with AFTRA marks a reversal in behavior for SAG and AFTRA leaders, who had feuded so bitterly over jurisdiction that AFTRA moved to negotiate its own primetime deal with the congloms in March — the first time in 27 years that the contract had not been jointly negotiated. At that point, AFTRA declared it could no longer trust SAG toppers in the wake of their alleged support for an actress on “The Bold and the Beautiful” seeking to decertify AFTRA as the show’s bargaining agent in order to give SAG jurisdiction.

AFTRA subsequently negotiated a new three-year primetime contract with the AMPTP in May, and AFTRA members ratified the primetime deal in July with 62% support — following an especially acrimonious campaign by SAG to persuade AFTRA members to vote down the deal.

Sunday’s SAG meeting was the first since guild members voted last month to push the Membership First faction out of power after a three-year run. During the campaign, the Unite for Strength slate hammered Membership First for bungling the feature-primetime negotiations by alienating AFTRA and leaving SAG de-leveraged at the bargaining table.