According the press release sent out through the Black House camp on Friday afternoon, Machida turned down the bout because he felt four weeks was inadequate time to prepare for a fight with the current light heavyweight champion.
"I want to serve the UFC and recapture the belt. I always respect my opponent," Machida stated. "For those reasons, I must prepare myself in the manner I believe in."
After defeating Ryan Bader via knockout at UFC on FOX 4 on Aug. 4, Machida was slated for the next shot at the light heavyweight belt, following the planned Sept. 1 Jones-Dan Henderson fight.
In the wake of Thursday's UFC 151 cancellation, UFC president Dana White said that Jones would instead fight Machida on Sept. 22 in Toronto.
According to Friday's press release, Machida wanted to take the fight on the Oct. 13 event in Rio de Janeiro. The UFC instead offered the title shot to Vitor Belfort, who accepted and will fight Jones in Toronto.