The welterweight bout would headline the UFC 303 card in Las Vegas, White told reporters after Saturday's UFC 300 event.
Irishman McGregor (22-6) has not fought since the clean break in his tibia resulted in a second TKO loss to Poirier in a row in July 2021. The injury required the former UFC featherweight and lightweight champion to undergo surgery.
Former Bellator lightweight champion Chandler (23-8) also lost to fellow American Poirier in his last fight in November 2022.
The fight has been teased by the UFC for more than a year, with McGregor and Chandler coaching opposing teams in their MMA-based reality show 'The Ultimate Fighter' last year.
McGregor announced the same date and opponent for his next bout in a video posted on X last December, calling it the "greatest comeback of all time."
