Dustin Poirier will face Conor McGregor at UFC 264 in Las Vegas this year.

The much-anticipated trilogy fight will take place at the T-Mobile Arena on July 10, UFC president Dana White confirmed on Wednesday.

"I am so happy to finally be able to say: Vegas is back," he said in a video posted on social media.

"This summer, Las Vegas is back open for business and on July 10, UFC 264 will be at the T-Mobile Arena at 100 per cent capacity.

"This card will be headlined by the third fight between Dustin Poirier and Conor McGregor."

The update comes after McGregor claimed the bout was off on Monday during an expletive-laden exchange on Twitter.

Poirier claimed victory in their previous showdown at UFC 257 in January in Abu Dhabi with a second-round knockout, after which McGregor conceded the result was "a tough one to swallow".

McGregor, who described his opponent's performance three months ago as "phenomenal", stopped the 32-year-old American in 106 seconds in their first encounter in September 2014.

The former two-weight world champion, who is also 32, has not won a UFC bout since January last year.