Khabib Nurmagomedov has thanked Dana White and the UFC for their support and understanding as his retirement was confirmed.
Khabib, who boasts a 29-0 record in the UFC, announced after his most recent victory against Justin Gaethje last October he was quitting the sport.
The fighter's father and coach, Abdulmanap, passed away earlier in 2020 and Khabib said: "There's no way I'm going to come here without my father."
UFC president White retained hope of changing his star performer's mind, but he accepted defeat on Thursday.
White posted on Twitter following a meal with Khabib that he was "officially retired".
The UFC chief also thanked for the Russian for his efforts, and those feelings of gratitude were reciprocated by Khabib in his own social media post.
"It was a good dinner with some great people," he wrote on Instagram. "@danawhite thank you so much brother and the entire @ufc team for the opportunity to prove myself, you guys have changed many live forever because of this sport.
"Dana - I'll never forget your attitude towards me, my father did not forget and my sons will remember you. Today there was a real conversation between real men.
"Also thank you to all team, sparing partners (sic) and all fans. I hope you will accept my decision and understand me."