A group led by Carolina Hurricanes owner Don Dundon has reached a tentative agreement with Paul Allen's estate to buy the Trail Blazers and keep the team in Portland.

Dundon confirmed the agreement in a text exchange with The Associated Press on Wednesday. His group includes Portland-based Sheel Tyle, the co-founder of investment firm Collective Global, and Marc Zahr, co-president of Blue Owl Capital.

The NBA board of governors must ratify any final purchase agreement. ESPN reported Wednesday the deal was for $4 billion US. Dundon did not reveal the terms of the sale to the AP.

CNBC earlier this year valued the Trail Blazers at $3.65 billion. In March, the Boston Celtics sold for $6.1 billion.

Dundon, 53, bought a stake in the Hurricanes in 2017 and became the majority owner in 2018. He is chairman and managing partner of the Dallas-based firm Dundon Capital Partners.

Allen's estate announced in May it had begun the process of selling the Trail Blazers. The billionaire co-founder of Microsoft, who died in 2018 at age 65 from complications of non-Hodgkin lymphoma, originally bought the Blazers in 1988 for $70 million.

Allen also owned the NFL's Seattle Seahawks and was a co-owner of Major League Soccer's Seattle Sounders.

Since his death, Allen's sister, Jody Allen, has served as chair of both teams and is a trustee of the Paul G. Allen Trust. Paul Allen stipulated in his will the eventual sale of his teams, with the proceeds given to philanthropic endeavours.

The estate has not announced plans for the sale of the Seahawks or the 25 per cent stake in the Sounders.

Jody Allen reportedly rebuffed an offer to buy the Trail Blazers from Nike co-founder Phil Knight for more than $2 billion in 2022. At that time, there were no ongoing discussions about the sale of the teams, she said in a rare statement.

The Trail Blazers joined the NBA as an expansion team in 1970 and won their lone NBA championship in 1977.

Last season, the Blazers finished 36-46 and missed out on the playoffs for the fourth straight year.

A spokesperson for the Carolina Hurricanes said Dundon was "excited about the opportunity" to buy the Trail Blazers, and added that the move will not affect the NHL team.

The Hurricanes, based in Raleigh, N.C., have made the playoffs in each of the last seven seasons.