Upcoming Marvel Cinematic Universe sequel Spider-Man 4 is shifting into "advanced" pre-production, a new report claims.The report comes courtesy of a tweet by the Cosmic Circus' Alex Perez. In the tweet, Perez said that sources close to the as-yet-untitled fourth Spider-Man installment have confirmed that pre-production on the movie recently ramped up. These same sources also allege that there are still some behind-the-scenes issues being ironed out by Marvel Studios and Sony, the specifics of which remain unclear. Perez closed by suggesting that an announcement from Sony regarding Spider-Man 4 "could be imminent," depending on whether the studio is ready in time for December's Comic Con Experience event. Neither Marvel Studios nor Sony have publicly commented on Spider-Man 4's status, which means this report should be taken with a grain of salt for now.Related: RUMOR: Marvel Studios Killed a Spider-Man/Venom Symbiote Storyline

That said, the buzz surrounding Spider-Man 4's pre-production progress tracks with recent rumblings that star Tom Holland has closed a deal to appear in the film. Holland is said to be locked in to reprise the Peter Parker/Spider-Man role for at least one more movie, however, it's unclear if his contract extends to any further sequels. It's equally uncertain whether the English actor is onboard to play the wall-crawler in other projects set in the wider MCU, although his deal supposedly doesn't extend to any of Marvel Studios' Disney+ shows. Marvel Studios and Sony remain tight-lipped regarding whether Holland is officially returning for Spider-Man 4, as does the star himself.

Sony's Original Plans for Spider-Man 4

Should Spider-Man 4 swing into theaters as planned, it will mark the first time Marvel's iconic superhero has headlined four solo movies of his own. Tobey Maguire came close to achieving this milestone with the planned fourth entry in Sam Raimi's Spider-Man series, however, that film was ultimately abandoned in 2010. Details of Raimi's Spider-Man 4 story have continued to surface since the production's cancelation. This includes confirmation that it would have finalized the break-up between Maguire's Peter Parker and Kirsten Dunst's Mary-Jane Watson.

Related: Tom Holland's Peter Parker Enters the Spider-Verse in Jaw-Dropping Fan Animation

Storyboard artist Jeffrey Henderson also recently revealed that Spider-Man 4's opening was set to be a montage featuring several classic Spidey foes. "We were going to open the movie with this montage of all the villains we knew that [director] Sam [Raimi] would never be able to use in Spider-Man movies… because Peter [Parker], now that MJ has gone, he has finally made peace, and he loves being Spider-Man," Henderson said. "He's actually enjoying it. So we were going to try to do The Shocker, Mysterio, The Stilt Man, and that kind of stuff."

Source: Twitter