Dr Pita Sharples believes Labour is wasting Shane Jones' talents and says unless Mr Jones leads his party, he's done for in politics after the election.
The pair are shaping up against each other in the Tamaki Makaurau electorate where the latest Te Karere Digi-Poll survey has given the Maori Party co-leader a commanding lead over Mr Jones.
In August, Mr Jones said he'd reconsider his political future if he didn't win the seat.
Yesterday, Dr Sharples echoed retiring Labour MP Mita Ririnui's view that Mr Jones could lead the party.
"I think he needs to be leading and I don't think that Labour is ready to make him a leader at this time.
"He won't stay if there's no sign of leadership."
"I think he's got a few rough edges he'd have to curb. His smart one liners can bring down a city, on the other hand it can also probably win a country. He'd definitely be a good leader, he's a bright boy."
The Maori affairs minister said he considered Mr Jones a friend, that said he knew enough about him to say Mr Jones liked being a boss.
"What I would like to see, is him excel. I don't care where it is because his talents aren't being used [now]. If he stays in politics he's got to have a leadership role, and if he doesn't get that role he should leave and go somewhere else."
Labour blundered by greenlighting Mr Jones' Tamaki Makaurau candidacy instead of giving him a safe seat such as Manurewa to run in, Dr Sharples said.
Yesterday, Mr Jones wouldn't be drawn on his future.