Dana White said UFC 249 is "100 per cent on" after Justin Gaethje replaced Khabib Nurmagomedov as Tony Ferguson's opponent in the main event.

Unbeaten UFC lightweight champion Khabib was originally set to face Ferguson in the blockbuster title bout in Brooklyn on April 18 before the coronavirus pandemic scuppered those plans.

Travel restrictions have prevented Khabib from entering the United States and Dubai, but the Russian superstar had not given up hope of fighting Ferguson as White looked into an alternate location.

The location of UFC 249 – set to be staged without fans – remains undisclosed, however Ferguson (25-3) will now step into the octagon against fellow American Gaethje (21-3) for the interim lightweight championship.

White wrote via Twitter on Monday: "The fight is signed and is 100 per cent ON LIVE on ESPN somewhere on EARTH!!!! @TonyFergusonXT vs @Justin_Gaethje is LIVE on @espn+ PPV April 18th for the interim lightweight belt!"

Gaethje, who has claimed three consecutive finishes over Donald Cerrone, Edson Barboza and James Vick, Tweeted: "#forthepeople I'm terrified and I f***** love it #ufc".

Coronavirus has wreaked havoc globally, bringing sport to a standstill following the postponement or cancellation of major events such as the Olympic Games, Euro 2020, Wimbledon and more.

More than 74,000 people have died around the world, with over 1.3million confirmed cases.

In the United States, there have been in excess of 10,700 casualties and 364,000 confirmed cases.