McGregor, who was ranked as the highest-paid athlete in sport by Forbes this year, will cover the costs of the team - 27 athletes and 20 coaches - who are travelling to Sofia in Bulgaria for the tournament from July 29 to August 1.

He sent a message to IMMAA, wishing the young athletes luck at the Championships.

"Wishing the Irish squad the very best of luck in their quest at the World Championships this year," said McGregor.

"From the fighters to the coaches, I know the future of our fighting nation is in excellent hands.

"Fight with the pride of the Emerald Isle, team! 

"We are all with you, good luck!"

The young team were captured on camera reacting to the message from McGregor.

At the 2019 Youth World Championships, Ireland brought the second-largest squad and won two gold, three silver and three bronze medals.

McGregor is one of the most famous MMA fighters in history, rising to stardom after a 13-second win against Brazil's José Aldo.

He has won three and lost three of his past six bouts, with the Irishman set for a rematch against the United States' Dustin Poirier on July 10.

McGregor has been the subject of various controversies during his career, including being charged with numerous driving offences and in connection to violent incidents outside of the octogon.