UFC fighter Justin Willis came under fire online after making comments about Aboriginal people. (AAP)

UFC fighter Justin Willis came under fire online after making comments about Aboriginal people. (AAP) Source: AAP

African American UFC fighter Justin Willis has come under fire online after making comments about Aboriginal Australians during a post-fight interview.

The Heavyweight fighter, nicknamed ‘Big Pretty’, fought at the same event as Tai ‘Bam Bam’ Tuivasa, the first Aboriginal fighter to headline a main event in the UFC.

Willis told the media after his Adelaide fight with New Zealand's Mark Hunt on Sunday, “Aboriginals are dark like me".

"I'm talking about the real Aboriginals, Aboriginals are dark like me,” he said.

“The ones that are being set aside in Australia right now... I'm talking about stuff that is real. And a lot of people who are fake don’t like that.”

Online, social media users voiced their frustration with Willis. One person said, "If you make tea and you add heaps of milk, it's still tea tho [sic]". Another said "this guy needs a history lesson".

The comments to media came after the UFC's only Aboriginal fighter celebrated his cultural identity with a big entrance to the ring.

Tuivasa followed a group of local Aboriginal dancers, with the Aboriginal flag around his shoulders - a tradition since last year after the UFC change their rules to allow the flag. He lost to Brazil's Junior dos Santos.

The 25-year-old Tuivasa who grew up in western Sydney made history on Sunday by becoming the first Aboriginal person to fight in a UFC main event.

The heavyweight fighter, who also has Samoan heritage, has vowed to push for the UFC to have regular Welcome to Country ceremonies after holding one in the week leading up to the fight.

“People who know me personally know how much my cultures mean to me… This is the first ever Welcome to Country done in the UFC in Australia,” Tuivasa wrote on social media.

“I want this to be recognised and make sure this happens every time there is an event on Australian soil. Cause this is our land and we are the first people of his nation and this needs to be known worldwide.”

There was hostility between Willis and Tuivasa during the weigh-in, which all fighters for the event attended, with Tuivasa yelling “I’ll f***ken smash you both!” to Willis and his team.

Last week, Willis posted a video showing him interacting with some Aboriginal men in Adelaide.

He asked them about Aboriginal history in Australia and made comments about not seeing enough Aboriginal people during his trip to the South Australian capital.

"We are all united in this country," the person he was talking to said.

Willis dedicated his win to these men, saying on social media "they were a big part of my inspiration".

Tuivasa made his debut in November last year, and in the past 12 months has fought in nine matches and increased his ranking to number 11 in the heavyweight division after an undefeated streak.

Despite the loss to Dos Santos, his ranking remains at 11.

NITV News requested comment from Willis.