Donald "Cowboy" Cerrone is sick of waiting for Conor McGregor to ink a fight contract so they can brawl once and for all ... telling the Irishman, "Sack up, bitch. Sign the f*cking paper."
Cowboy pulled no punches during an interview with ESPN's Brett Okamoto ... saying he's "annoyed" that Conor teased the fight on social media, but now he won't make a deal.
Cerrone says he's been in talks with UFC about fighting McGregor since January as a co-main event in either April or July .