The centre-forward's current contract expires at the end of the season.
However, Comolli today suggested an agreement over an extension has long been in place.
He said at a media briefing at Juventus Stadium: "We've reached an agreement with the player: we'll talk at the end of the season.
"We don't expect anything special; we've already reached an agreement with Dusan, which was already reached last summer with (Giorgio) Chiellini and (Francois) Modesto.
"An agreement has already been reached, so we're certainly confident about this situation. I don't think any Italian club can pay like the Premier League, but that doesn't mean we don't want to be competitive.
"And we, like the others, must respect the 70% limit of the UEFA squad cost ratio."