Hollywood's Academy of Motion Picture Arts and Sciences invited Cohen to attend the prize presentation on behalf of his film "Hugo," which is up for 11 Oscars including Best Picture.
However, the academy said this week Cohen is not welcome on the red carpet or inside the venue dressed as the militaristic, Middle Eastern character to promote his upcoming movie "The Dictator."
"While I applaud the academy for taking away my right to free speech, I warn you that if you do not lift your sanctions, and give me my tickets back by 12 p.m. Sunday, you will face unimaginable consequences!" Cohen, dressed as the fictional Gen. Aladeen, said in a video message Friday. "On top of all this, I paid Hilary Swank $2 million to be my date, and she will not refund a penny."
Swank famously fired her manager last year after she was criticized for taking money to be at a party for Chechen President Ramzan Kadyrov, a politician accused of torturing dissidents, killing opponents and encouraging the abuse of women.
The actress later apologized for being a guest at the event and vowed to donate her six-figure appearance fee to charity.
After Cohen's "Dictator" video clip debuted online Friday, Oscar telecast producer Brian Grazer told TV's "Extra" the actor can wear what he wants.
"We're thrilled to have him and he'll be on the red carpet dressed as 'The Dictator,'" Grazer said.