Barcelona have set Ronaldinho's asking price at £30 million.
"I only say that Ronaldinho is worth more than 40 million euros" Laporta said in Gazzetta dello Sport.
"He has never created the slightest problem and I'm sure he will return to how he was before, as soon as he is well.
"He just needs to find new motivation, but it's no foregone conclusion that he has to leave because he can find this with us, given that his contract runs until 2010."
Laporta also confirmed that English clubs have shown an interest in Ronaldinho but he believes Milan remains his most likely destination, should the former Paris Saint-Germain star opt to leave.
"We have had many offers from England, but Milan is the team who have showed the best interest," added Laporta.