The 19-year-old only signed his current deal eight months ago but has grown in stature at Old Trafford since then.
Williams made his first-team debut in September's EFL Cup win over Rochdale and has gone on to make a further 25 appearances in all competitions.
Having earned the full trust of boss Ole Gunnar Solskjaer, The Athletic claims that the England Under-20s international is in line for a huge pay rise.
The report suggests that Williams currently earns around £4,000 a week, but his new deal will reflect his importance to United's long-term plans.
Williams is in contention to start United's first game back after the Premier League's coronavirus-enforced stoppage. body check tags ::