Howard Stern announced that this season of "America's Got Talent" will be his last, and while some NBC insiders believe he simply may be engaging in brinksmanship, the shock jock insists that he'll leave the show when it goes on hiatus in September.

Speaking Wednesday on his SiriusXM radio show, Mr. Stern said the demands on his schedule left him with little choice but to bail on NBC's hit competition series after four seasons on the judges' panel.

"I gotta tell ya, I'm going through my own career evaluation right now…[and] I'm just too fuckin' busy doing 'America's Got Talent' and doing the radio show and everything," Mr. Stern said. "You know, something's got to give. NBC's already asked me what my intentions are for next year, whether or not I would come back. And I kinda have told them I think this is my last season. Not 'I think'—this is my last season."

Mr. Stern said NBC executives are planning to re-locate 'AGT' to Los Angeles in his absence. The network in 2013 moved the live shows to New York's Radio City Music Hall to accommodate Mr. Stern's Sirius schedule.

While Mr. Stern was adamant about his decision ("I've been on there four years. It's been fun. I think that's enough."), he said he isn't walking away from TV for good. "I have been made an offer in television that excites me. Excites me to no end," he said. "But I can't do 'America's Got Talent,' the radio show and this television opportunity."

Mr. Stern suggested that 'AGT' Executive Producer Simon Cowell actively covets his position, adding that the "American Idol" impresario "would be good at it." As it so happens, NBC once approached Mr. Cowell about returning to the U.S. airwaves; in an email exchange that took place in April 2014, NBCUniversal CEO Steve Burke told Sony Entertainment CEO Michael Lynton that "the right thing to do would be for [Cowell] to star in the show, not Howard Stern, and move it to Los Angeles (where it would be cheaper)."

The Burke-Lynton email exchange was unearthed in the Sony WikiLeaks hack.

Mr. Stern did not provide details about the proposed TV gig, but he did say that he would have to think long and hard about re-upping with Sirius before his contract expires in January. "The good people here at Sirius like me very much and they would like me to do the show some more," he said. "I gotta think that through and figure out what's best for me there."

Naturally, the overt mention of his contractual status may also be construed as a negotiating tactic, although it's hard to imagine Mr. Stern turning his back on an estimated annual salary of $80 million. (Per Forbes, he rakes in another $15 million by way of the "AGT" gig.)

Mr. Stern first signed with Sirius in October 2004, inking a five-year deal with the satellite radio company. He signed a five-year renewal back in December 2010. The following year, he joined "AGT" as a replacement for Piers Morgan.

"AGT" is the summer's most-watched, highest-rated TV series. Per Nielsen live-plus-same-day data, the show is averaging 10.7 million viewers and a 2.4 rating among adults age 18-to-49. Through the first five episodes of Season 10, "AGT" has generated some $49.4 million in ad sales revenue, according to iSpot.tv estimates.

Along with new integrated sponsor Dunkin' Donuts, some of the biggest "AGT" backers include The Home Depot, Toyota and Walmart.