The decision does not rule out, however, that the team could try to trade Williams.
King also mentioned during the interview his desire to re-sign both Brook Lopez and Thaddeus Young while staying under the threshold for paying the NBA luxury tax. Both Lopez and Young have contract options that allow them to become free agents on July 1.
If Williams, Lopez, Young and forward Joe Johnson each return to the team in 2015-16, the report said, the Nets would almost surely pay the tax.
"The goal is to try to be under the tax," King told Newsday.
"That's just the goal. How realistic? It may not be. If we end up being over the tax, so be it. We're not going to jeopardize our roster, jeopardize the team just to be under the tax. If a decision is made to make the team better then we'll do that."
The 30-year-old guard has two years and $43 million left on his contract.
Williams averaged 13 points and 6.6 assists per game for the Nets during the 2014-15 season.
- Will Green