When "Agents of S.H.I.E.L.D." was announced in 2013, one of its chief selling points was "it's all connected," a phrase that over the years has become a mantra for both Marvel and fans, underscoring that the threads of the cinematic universe weave through television and film. While there have been callbacks to Marvel Studios films on TV series, from "S.H.I.E.L.D." to "Agent Carter" to "Iron Fist," any sort of significant crossover between the two has yet to happen. However, Marvel Studios President Kevin Feige, that could change -- eventually.

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As Jeph Loeb, Marvel's head of television, explained last summer, the primary obstacle to such crossovers is the drastic differences in planning and scheduling between TV and film. “Television moves at an incredible speed," he said The other part of the problem is that when you stop and think about it, if I’m shooting a television series and that’s going to go on over a six-month or eight-month period, how am I going to get Mike [Colter] to be able to go be in a movie? I need Mike to be in a television show.”

But while some fans doubt the Marvel Cinematic Universe will ever overcome those barriers and become fully integrated, Feige now insists its bound to happen, just not anytime soon.

While promoting "Guardians of the Galaxy Vol. 2," Feige was asked if whether a character introduced on a Marvel TV series is ineligible to later appear in a film.

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“Not necessarily,” he told io9.com. “The future’s a long time. So, the truth is, I don’t really know, but there are a lot of TV shows being made, and hopefully we’ll continue to make a lot of movies. At some point, there’s going to be a crossover. Crossover, repetition, or something.”

While that certainly sounds as if a crossover isn't in the immediate future, Feige's comments may give some hope to fans longing to see the Defenders some day join the Avengers on the big screen.

In theaters now, writer/director James Gunn's "Guardians of the Galaxy Vol. 2" stars Chris Pratt as Star-Lord, Zoe Saldana as Gamora, Dave Bautista as Drax the Destroyer, Vin Diesel as Baby Groot, Bradley Cooper as Rocket Raccoon, Michael Rooker as Yondu Udonta, Karen Gillan as Nebula, Pom Klementieff as Mantis, Elizabeth Debicki as Ayesha, Chris Sullivan as Taserface, Sean Gunn as Kraglin, Glenn Close as Irani Rael and Kurt Russell as Ego.

The film will be followed July 7 by the release of "Spider-Man: Homecoming," the first co-production between Marvel and Sony, and then Nov. 3 by "Thor: Ragnarok."