Conor McGregor has been pictured on a drinking session with gangsters Andrew and Jonathan Murray.
It has emerged the Murray brothers, both of whom have a string of convictions, including for drug offences, flew to London on McGregor's private jet last week.
The Crumlin pair have posted pictures on social media of themselves and the MMA fighter out and about in the English capital.
They also posted snaps in McGregor's car and at the Fashion Awards at the Royal Albert Hall.
McGregor, who has a young son with girlfriend Dee Devlin, recently hit the headlines after singer Rita Ora posted a picture from the event of their "date night".
She was accused of being disrespectful towards the mother of his children.
Over the last month the Murrays have also filmed themselves on McGregor's luxury boat - named 188 after the amount he used to claim in dole - and on jet skis in Dun Laoghaire
At one point during their recent trip to London, the gangsters threw money at scantily clad women at the Cirque le Soir nightclub.
Footage, taken at around 1am on Wednesday morning, was also posted of McGregor throwing money at a hostess.
The group made their way back to McGregor's suite at the Berkeley Hotel, one of the most expensive in the city, for a party with around 10 women.
Andrew Murray (34) has convictions including possession of drugs for sale and supply, as well as theft and forgery.
Jonathan Murray (27) was involved in a brutal assault of a man in 2009 and has almost 50 convictions.
He was jailed for 18 months for his role in the assault in which Crumlin gangster Ian 'Mad Dog' Maloney danced on Joey O'Brien's head after coming across him at a restaurant.
However, the brothers mixed with A-list celebrities while in London, including F1 driver Lewis Hamilton and the singer Ora.
It is understood their night nearly came to a swift end when they were forced to wait outside the Chiltern Firehouse for an hour following a row with a bouncer.
They were eventually allowed into the restaurant.
The Murrays are childhood friends of McGregor and have become a part of the fighter's entourage.
They travelled to Las Vegas for his fight with Floyd Mayweather earlier this year and then partied with him after he lost the bout.
On November 30, McGregor appeared at Blanchardstown District Court to answer a speeding fine.
He was fined €400 after being charged with exceeding the 100kph speed limit on the N7 Naas Road at Rathcoole on March 31 this year, an offence under Section 7 of the Road Traffic Act 2004.
The MMA fighter apologised for the offence after the judge told him to take cognisance of other road users and reduce his speed.
"Yes, I apologise for that," he said.
"I wanted to show my respect by showing up here today, and I apologise. I'll pay the fine, thank you."
Speaking to the Herald after the court case ended, McGregor denied rumours that had been circulating on social media that he had been involved in a bust-up with an associate of a gangster.
"It's all b*****ks," he said as he left the court.