Ariel Helwani reacts to Conor McGregor announcing he will return to the Octagon on January 18 with an opponent still to be determined. (0:52)

Conor McGregor has announced his comeback date.

The former two-division UFC champion said Thursday at a news conference in Moscow that he will return to the Octagon on Jan. 18 in Las Vegas. McGregor said he knows his opponent but would not reveal his name, because if he did, the UFC would "flip" it.

"Ask the UFC who the opponent is, because I do not give a f--- who the opponent is," McGregor said, speaking at an event for his sponsor Parimatch, a Russian betting website.

Sources told ESPN that Donald Cerrone and Justin Gaethje are the top two candidates to fight McGregor. Cerrone is the front-runner, sources said.

UFC president Dana White told ESPN's Brett Okamoto that the Jan. 18 is being targeted but that "no deals are even close to being signed."

McGregor, UFC's biggest star, promised a "fully focused" version of himself for the fight at T-Mobile Arena, which is in 12 weeks. He said he has already started his preparation, including going to bed early every night and waking up early every morning.

The return bout, McGregor said, will be "the beginning of my season," and he plans to fight three times next year. McGregor said after January that he will seek to face the winner of the UFC 244 main event between Nate Diaz and Jorge Masvidal. McGregor is picking Diaz to win that fight. After that, McGregor said he wants to fight for the UFC lightweight title against the winner of a potential matchup between champion Khabib Nurmagomedov and Tony Ferguson.

McGregor (21-4) has not fought since falling by submission to Nurmagomedov at UFC 229 in October 2018. The Irishman said he wants the Nurmagomedov rematch to be in Moscow. Nurmagomedov hails from the Russian republic of Dagestan.

"That is the bout we want," McGregor said. "We want this bout in Moscow. The people of Russia deserve this bout to take place. The people of the world deserve this bout to take place."

McGregor, 31, has not won an MMA fight since 2016, when he beat Eddie Alvarez to win the UFC lightweight title. With that victory, McGregor became the first fighter in UFC history to hold belts in two weight classes concurrently. After that, McGregor moonlighted in 2017 as a boxer, fighting and losing to Floyd Mayweather Jr. by TKO in one of the most financially successful pay-per-view events ever.

At the news conference, McGregor said he regrets not being focused on his fight with Nurmagomedov and vowed to return to his previous form beginning in 2020.

"The people who believe in me deserve better," McGregor said. "It is an insult to the people that believe in me that I am not fully committed. So now I am coming back and I'm fully committed. And I am eager to come back and show the best of myself for my fans around the world."

During this layoff, McGregor has faced several legal issues, including most recently a second allegation of sexual assault, according to The New York Times. A publicist for McGregor has denied the allegation.