The 22-year-old linked up with his national side despite not playing for Chelsea since October 28 because of a hamstring injury sustained ahead of the Premier League clash with Burnley.
However, Pulisic has been deemed unfit to play against Wales in Swansea on Thursday and Panama in Austria next Monday, however, and has now dropped out of the squad.
NEWS: Gregg Berhalter announces that @cpulisic_10 will return to @ChelseaFC to continue working through his injury rehab.— U.S. Soccer MNT (@USMNT) November 11, 2020
It was great having you in with us this week, Christian!
Speaking at a pre-match news conference on Wednesday, United States head coach Gregg Berhalter said: "Christian is a big part of our group.
"He has been working through an injury, but he really says a lot that he wanted to come into camp, be around the guys and continue to be a leader with this team."
Pulisic had featured five times for Chelsea in all competitions this term before suffering his latest injury setback and scored in his most recent match, a 4-0 Champions League win over Krasnodar.
He has yet to get off the mark in terms in three Premier League outings this term and has created only once chance from open play.
Asked if Pulisic will be available for Chelsea's trip to Newcastle United on November 21, Berhalter said: "It is hard to speculate."
USA have triumphed in their last three games by an aggregate score of 9-1 but last won a match against one of England, Wales, Northern Ireland or Scotland in May 2012, beating the latter 5-1.