Perez is delighted to see James revive his career on-loan at Bayern Munich this season under the guidance of former Real coach Jupp Heynckes.
However, Diario Gol says he plans to use the Colombia captain as a makeweight in negotiations for Robert Lewandowski.
Perez has enquired about a price for the Poland striker and been quoted €150m. In order to drive down the cash valuation he is willing to include James in his offer.
Perez is prepared to value James at €50m, so to bring down Lewandowski's cash component to €100m.