The source spoke to The Associated Press after the judge investigating the case had his first meeting with Rees-Jones in the Paris hospital where he is recuperating.
The source, who spoke on condition of anonymity, had seen the written report of Judge Herve Stephan's meeting with Rees-Jones.
No further details from the meeting were immediately available.
Doctors had said all along that the large doses of anesthesia given to Rees-Jones during surgery, along with the trauma of the accident, might affect his memory.
The judge plans further meetings with Rees-Jones, and investigators clearly hope his memory might improve.
Investigators want Rees-Jones to shed light on the behavior of driver Henri Paul, who was legally drunk at the time of the Aug. 31 accident that killed him, Diana and her companion, Dodi Fayed.
Paul's body was on its way to Brittany today for a weekend burial in his
hometown, three weeks after the accident.