Phoenix Suns vice-chairman Jahm Najafi has called for Robert Sarver's resignation after the majority owner was found to have engaged in racist and sexist conduct at the workplace.

The NBA hit Sarver with a one-year suspension and a $10million fine this week, having interviewed 320 people after allegations emerged of inappropriate behaviour during his 18 years with the Suns.

The league stopped short of issuing a lifetime ban, however, leading four-time MVP LeBron James to declare: "Our league definitely got this wrong."

NBA commissioner Adam Silver said Sarver was "on notice" in the aftermath of the ruling, but Najafi does not wish to see Sarver stay on.

In an open letter to the Suns players and staff, Najafi said he had no interest in becoming the next managing partner, but would "work tirelessly to ensure the next team steward treats all stakeholders with dignity, professionalism and respect".

"Due to the NBA's investigation and findings, I have no choice but to speak up on behalf of the hundreds of you that have been impacted by your interactions with Robert Sarver," the letter from Najafi read.

"There should be zero tolerance for discriminatory actions of any level, in any setting, let alone a professional one.

"There is no question that the findings determined that Mr Sarver's lewd, misogynistic and racist conduct had a substantial negative impact on you and has no place in our society.

"Similar conduct by any CEO, executive director, president, teacher, coach or any other position of leadership would warrant immediate termination. The fact that Robert Sarver 'owns' the team does not give him a licence to treat others differently than any other leader.

"The fact anyone would find him fit to lead because of this 'ownership' position is forgetting that NBA teams belong to the communities they serve. Team investors are merely temporary stewards.

"If we, as sports leaders, are not held to the same standards, then how can we expect a functional society with integrity and respect on any level?

"I cannot in good judgement sit back and allow our children and future generations of fans to think that this behaviour is tolerated because of wealth and privilege.

"Therefore, in accordance with my commitment to helping eradicate any form of racism, sexism and bias, as vice-chairman of the Phoenix Suns, I am calling for the resignation of Robert Sarver."

Najafi has been critical of Sarver since the allegations were first reported last November, and is one of three vice-chairmen at Phoenix, where several other minority investors form part of the ownership group.