Ariana Madix Refuses to Film 'Vanderpump Rules' Scenes with Tom Sandoval

Tom Sandoval and Ariana Madix coming face-to-face is not happening -- not for cameras, at least -- as we've learned the 'Vanderpump' exes haven't shot a one-on-one scene together since filming started for the next season.

Sources connected to the show tell TMZ ... Ariana is refusing to share the screen with Sandoval, and keep in mind, they've been filming for season 11 since late June. The prospects of that changing don't look good, either, because she's just not interested in talking to the guy.

Contrary to a report, we're told Ariana hasn't spoken to him directly since last season's tense reunion -- and they're only communicating through other people.

Our sources say production is currently slated to wrap around the first week of September, so producers are in crunch time ... and we're sure a scene with Tom and Ariana is at the top of their to-do list.

As we reported, the closest they've gotten to each other since production began was at SUR earlier this month, where they both were in the building but steered clear of each other.

One thing Tom couldn't avoid was the wrath of Scheana Shay ... she ripped into him about Rachel Leviss, who's creating a whole other problem for producers.

We told you Bravo has her under contract to appear in the new season, but she's been MIA from all shoots since ending her 100-day stay in a wellness facility. The issue for Bravo is ... under California law, she can choose to walk away.