The Toffees are closing in on the Argentine defender who watched Sunday's 2-0 defeat to Manchester City from the Goodison Park stands.
In the wake of the match, Martinez said that 24-year-old Mori could join Everton from River Plate by Monday night as he looks to add to his squad before the close of the transfer window on September 1.
"No (deal yet)," he said.
"Obviously he's here, and we're going to meet over the next 24 hours and see if we can conclude a deal with his club River Plate.
"But there's nothing to announce yet."