In a video posted to social media, White said Whittaker and Du Plessis will square off on July 8 in Las Vegas and the winner will face 185-pound champion Israel Adesanya later this year. According to White, that fight will likely take place in Sydney.
Whittaker (24-6) has lost to Adesanya twice since 2019, but has pressed the issue on a trilogy thanks to a 12-0 record in the UFC's middleweight division against anyone other than Adesanya.
The Australian contender is coming off a convincing decision win over Marvin Vettori in September.
Du Plessis (19-2), of South Africa, is 5-0 in the UFC since his debut in 2020 and has picked up wins over the likes of Darren Till and Derek Brunson. Adesanya has recently expressed interest in fighting Du Plessis. Both were born in Africa.