The actor dished on his feelings over their glaring absence from "Fuller House" just earlier this week -- admitting to "Glee" stars Kevin McHale and Jenna Ushkowitz on their podcast that he was, in fact, "angry" over their decision to not star in the revived Netflix series.

He says he and the rest of the OG cast didn't stay in close touch with them post-'FH' -- with the late Bob Saget being the exception, he notes -- which probably didn't help when it was time to approach them about reprising their role as Michelle ... something they declined.

JS explains, "When I did 'Fuller House,' they didn't want to come back and I was angry for a minute, and that got out." He goes on to explain that there was a misconception that the girls hated their childhood and their time on "Full House" by extension ... but says that's BS.

John adds, "But they said, 'We loved our childhood. We loved being with you. We miss Bob.'" He also mentions a recent visit they made to his home when they brought grub/sage.

Since then, John says he and the Olsen twins have "stayed very close." It sounds like this all might've happened after Saget's death last year -- which, in hindsight, is a shame ... 'cause John himself has also conceded that he might've been able to get the twins back on TV if he'd gone about it the right way. Namely, talking to them personally ... which he didn't.

As John explained to THR in 2016 -- when "Fuller House" was first launching -- Mary-Kate was apparently somewhat interested in "Fuller" and wanted him to try to convince Ashley, who was wearier of getting back into acting. He also says they told him never heard an official request from anyone ... despite him thinking he'd gotten a hold of their agent.

In the end, it appears there was a communication breakdown ... and some hard feelings in the wake of not getting them. But, like John make sure to clarify, he's got nothing but love for the Olsen twins ... who've arguably moved on to bigger and better things in fashion, etc.