UFC has not yet determined a site for the event, but venues in Texas, Chicago, Las Vegas and Rio de Janeiro are being considered.
Promotion president Dana White confirmed plans for the bout to USA Today on Monday.
"These guys are two of the most amazing, gravity-defying athletes in the sport," White told the newspaper. "I am so pumped for this fight."
Aldo (22-1) successfully defended his 145-pound title on Saturday when he beat former lightweight champion Frankie Edgar by unanimous decision at UFC 156 in Las Vegas.
Immediately after that fight, Pettis sent White a text expressing his desire to fight Aldo.
"It's no disrespect to Aldo that Anthony wants to fight him," Pettis' trainer, Duke Roufus, told ESPN.com on Monday. "It's actually a sign of respect for Aldo.
"He's one of the best fighters in the world, and Anthony wants to fight the best."
Roufus also said that Pettis' goal is to capture the featherweight and lightweight titles.
Lightweight titleholder Benson Henderson is set to defend his belt against ex-Strikeforce champion Gilbert Melendez on April 20 in San Jose, Calif. Pettis is currently slated to face the winner of that fight.
But with Pettis (16-2) now scheduled to fight for the featherweight belt, UFC officials have not yet said whether he will remain next in line for a lightweight title shot.
Pettis, a native of Milwaukee, put himself in position to fight for the lightweight title on Jan. 26 when he knocked out Donald Cerrone in the first round of an elimination bout.
Despite being next in line for a 155-pound title shot, Pettis expressed uneasiness about waiting for the Henderson-Melendez outcome. Roufus cited his fighter's previous experience waiting for a title shot as the reason.
"What if the guy who wins the Henderson-Melendez fight gets hurt or it's a close decision, when does [Pettis] fight?" Roufus said. "He's been in that situation before. So, he's a little gun-shy about that."
Pettis, who entered UFC as the reigning WEC lightweight champion in 2010 when the promotions merged, was slated to face the winner of Edgar-Gray Maynard II in 2011. But that fight ended in a draw, prompting UFC officials to schedule a rubber match between them.
Shortly after UFC announced the third fight between Edgar and Maynard, Pettis opted to face then-fellow lightweight contender Clay Guida. The two fought on June 4, 2011, in Las Vegas.
Guida defeated Pettis by unanimous decision. Pettis, however, has since reeled off three wins in a row to get back in the lightweight title picture.