Galliani had negotiations with Kaka’s agent in Italy this week and confirmed there was a plan in place to reunite with the player who was sold for €65m in 2009.
“It is very difficult,” said Galliani.
“The negotiations are all to be done, there are a thousand difficulties that could well make it impossible.
“As always, the problem is money. Milan cannot afford some wages, especially as in Spain they have a different fiscal structure.
“The law there has changed for future wages, but the contracts that were already signed are still valid under the old tax code.”