WBO world welterweight champion Manny Pacquiao will fight Great Britain's Amir Khan on 23 April.
The bout has been arranged after Pacquiao's followers on Twitter voted Khan as the opponent they would like to see the Filipino fight next.
"This is what the fans wanted," Pacquiao, 38, said on social media.
Khan, 30, also confirmed the fight but, although Pacquiao has said his next fight would be in the United Arab Emirates, no venue has been announced.
Speaking on a social media video, Khan said the UK, Dubai and US were being looked at as possible locations and that they "should find out in the next couple of days".
The Briton, who won silver as a lightweight at the 2004 Olympics, beat compatriot Kell Brook, Australia's Jeff Horn and American Terence Crawford with 48% of the vote carried out by Pacquiao.
Khan's last fight was in May 2016 when he was knocked out by Mexican Saul 'Canelo' Alvarez.
Six-weight world champion Pacquiao retired in April last year but returned to claim his belt by beating Jessie Vargas in November.
BBC Sport's Luke Reddy
Khan's typically fast work will come up against a man who - in his prime, at least - dazzled the world with his own hand speed.
Pacquiao of course is still a world champion, but there will be some British fight fans who would rather see Khan face off against bitter rival Kell Brook - who himself has gone elsewhere and meets Errol Spence in May.
Fans of trash talk may also be disappointed as a clear respect exists in the Khan-Pacquiao relationship - the pair have sparred one another under trainer Freddie Roach, whom Khan left in 2012.
There is no doubt Pacquiao's standing in the sport will give Khan the opportunity to take a giant leap forward from his brutal KO defeat by Saul 'Canelo' Alvarez last time out.
One point on the marked date - 23 April is a Sunday. So it does look like this will take place east of the UK, so the time difference will suit British and American viewers on a Saturday night.
Will it happen? It's a tight turnaround for two stellar names, especially accounting for the huge promotional commitments they will also have to squeeze in. If it does of course, fans can look forward to Nicola Adams, Ricky Burns, Khan and Anthony Joshua fighting on successive weekends.