A South Sudanese-Australian man who's been accused of lying about his role as a youth mentor has blamed the growing scandal on a "tribal conflict", even as senior members of the community continue to pour scorn on his claims.

Nelly Yoa said he had been mentoring young Sudanese gang members in and out of prison, in addition to trying out for Premier League football clubs and training with an AFL team.

It was with these credentials that he used a New Year's Day opinion piece for The Age to claim that South Sudanese teens were causing "great harm and fear" in Melbourne.

In the piece he took aim at South Sudanese community leaders, the Victorian Government and the police for not doing enough.

He was subsequently interviewed by a range of media outlets, including the ABC.

The row over African crime in Melbourne intensified when Greg Hunt, a senior federal cabinet minister from Victoria, said violence was "out of control" in some areas, and tougher sentencing laws were needed.

That sparked similar reactions from other senior Liberals, including Prime Minister Malcolm Turnbull and Home Affairs Minister Peter Dutton, who said some Victorians were afraid to go out to dinner at night because they might be attacked.

Victoria Police conceded there was a problem within the commuity following a series of high-profile crimes blamed on African-Australian men, including the trashing of an Airbnb property at Werribee.

But Mr Yoa's credibility began to unravel this week after concerns were raised that he was overstating his influence.

"Nelly is not in the community," said Richard Deng, a senior South Sudanese leader in Melbourne.

"We have tried several times contacting him. We have tried many times to get him to come and talk to the community leaders.

"He has actually refused to talk to us."

The saga has become an unwelcome distraction for Melbourne's South Sudanese community as it grapples with allegations of gang violence.

"We should be talking about the challenges we're facing," Mr Deng said.

"We have, as a community, greater issues that we are dealing with."

In response to the criticisms, Mr Yoa said he had never been contacted by either Mr Deng, or Kot Manoah, the chairman of the South Sudanese Community Association in Victoria.

"I've never said I was a community leader, I've always [described] myself as a community member," he said.

'Conflict' within Melbourne's Sudanese community: Yoa

Mr Yoa said he was the victim of a personal vendetta and said members of the South Sudanese community based in Melbourne's south-eastern suburbs could vouch for him.

The ABC contacted one leader Mr Yoa suggested, but is yet to receive a response.

Mr Yoa also claimed the current dispute had roots in an old tribal conflict.

"The Sudanese community that is based in the western suburb[s], they come from a tribe called Dinka," he said.

"The other South Sudanese community that is based in the south eastern suburbs, where I'm based, they come from the Nuer tribe.

"There's a conflict going on between the two tribes and this dates back to the current situation in Sudan."

Mr Deng encouraged Mr Yoa to seek out Sudanese community organisations.

"We want him to contact community leaders. Let him come talk to us so that we can really help him. If you want to help people, we know where we can direct him," he said.