'Orange Is the New Black' Star -- Forget Separation ... Let's Skip Right to the Divorce

"Orange Is the New Black" star Pablo Schreiber wants to rip off the band-aid -- demanding a straight up divorce ... after his estranged wife asked for a separation first.

TMZ broke the story ... Jessica Schreiber (a yoga instructor) filed for legal separation shortly before Christmas, citing irreconcilable differences. But Pablo -- who plays the corrupt drug-peddling corrections officer George Mendez on the show -- wants to skip the intermediary step.

It's gearing up to be an acrimonious split too -- as we reported, Jessica asked for full physical custody of their two sons (a 5-year-old and a 2-year-old).

Now Pablo -- Liev Schreiber's bro, btw -- is returning fire ... asking the court to block Jessica from getting spousal support. He also wants joint custody of their kids.

Interesting timing for Pablo to block a money grab -- Season 2 of OITNB is set to kick off shortly, which should mean more cash in his pockets.