The German-born Ghanaian international is almost certain to leave Fratton Park this summer but after discussions with the Serie A stalled, it is now unknown exactly what is in store for him.
"I don't think the talks can be considered closed," Boateng's agent, Mario Miele, told lalaziosiamonoi.it.
"Until a few days ago there was constant dialogue and everything seemed to be coming towards a conclusion, although Portsmouth were still asking for more.
"But since then everything has reached deadlock. I don't think everything is over, because no-one has told me that, so I suppose the interest is still there.
"We will have to wait and see what happens now over the coming days."