Referee Abdella El Achiri said he was going to report the incident to the Moroccan soccer federation, L'Equipe sports daily reported on Thursday.
"I was a bit surprised to see Barthez coming towards me on the pitch as he had been replaced at the interval," El Achiri said. "He came up to me, he insulted me and he spat at me."
The match was stopped when a brawl erupted in the 80th minute while the Moroccan hosts were leading 2-1, which was the final score.
"I'm going to report to my federation and it will be up to them to make a move," El Achiri said.
If found guilty Barthez, France's 1998 World Cup-winning goalkeeper, could be banned for several matches, L'Equipe said, adding that Olympique Marseille executive chairman Pape Diouf has sent an invitation to El Achiri to try to defuse the row.
More from rediff