According to JP Finlay of NBC Sports Washington, a source that spoke to Williams said: "He's not coming back. Period."
Williams did not attend offseason workouts or mandatory minicamp, and he is holding out of training camp. The 31-year-old veteran has two years and nearly $24 million remaining on his contract, per Spotrac.
Finlay's sources said Williams' holdout is only partially about money. Last week, Jerry Brewer of the Washington Post reported Williams has "trust issues" with the Redskins' medical staff.
As well, former Redskins cornerback DeAngelo Hall appeared on NFL Network and said Williams doesn't want to return unless changes are made to the training staff.
Williams has missed at least one game in each of the past five seasons, including three last season and a career-high six in 2018. Even so, the franchise left tackle has been named a Pro Bowler the past three campaigns.
The Redskins could fine Williams for not reporting, but sources told Finlay that Williams isn't concerned since he has earned nearly $100 million during his career.
When Williams signed a five-year, $68 million contract in 2015, it was the richest deal for an offensive lineman. He now ranks eighth among NFL offensive lineman in yearly salary at $13.6 million.
With Williams away from the team, the Redskins signed 36-year-old Donald Penn, who is a three-time Pro Bowler in his own right.
If Williams does not return, Penn is expected to vie for the starting left tackle job with Geron Christian, who was a third-round pick in 2018.
The winner of that competition may have the important job of protecting the blind side of rookie quarterback Dwayne Haskins if he is able to beat out Colt McCoy and Case Keenum to become the starting signal-caller.