Sean Penn Calls for Boycott of Oscars If Zelensky Snubbed from Telecast

Sean Penn is backing Amy Schumer's idea of having Zelensky beam in to the Oscars ceremony -- going so far as to say if it doesn't happen ... the show should be boycotted.

The award-winning actor -- who's got two statuettes of his own -- made the bold suggestion Saturday during an interview on CNN, which was delving into the humanitarian work he and his crew are doing in Europe as they work to offer relief and aid to fleeing Ukrainians.

Toward the end of the chat, anchor Jim Acosta asked SP what he'd like to see from the Academy Awards Sunday -- and the guy didn't hold back with his thoughts.

Check it out ... Sean is firmly behind the idea of having Zelensky and/or other Ukrainian leaders make an appearance during the telecast, saying there is nothing more important that Hollywood could do in a time like this.

He said some have argued politics should be left out of shows like this, and while he says he might agree with that in some respects ... he suggests the war transcends grandstanding.

Sean also says he's heard the Oscars producers have actually elected to NOT feature Zelensky -- something this year's Oscar co-host, Schumer, alluded to in a recent interview, this after she apparently floated it -- and goes on to say if that's the case ... he'll be pissed.