Former Inter Milan president Massimo Moratti insists they must get value for money if they're to lose Lautaro Martinez.
The Argentina striker is a top summer target for Barcelona.
"Lautaro out? If (Lionel) Messi comes, I'd accept it," said Moratti.
However, he later pointed out that "if that is impossible, I would sign (Paulo) Dybala."
The latest offer from Barca is for €60m cash plus a selection of four players from Ivan Rakitic, Arturo Vidal, Nelson Semedo or Samuel Umtiti.
Barca are willing to include two of those four listed in their offer for the Inter striker.