Udinese have informed Serie A rivals Napoli they have until Monday to wrap up a deal for Gokhan Inler.
The two clubs reached an agreement for the Switzerland international in June, but slow progress has been made since then.
The 27-year-old is yet to agree personal terms, meaning discussions have dragged on longer than expected.
Udinese are growing impatient at the lack of activity and have called for the saga to be resolved one way or another by the start of next week.
"If Napoli does not finalise the deal by Monday, Inler will join us in pre-season training," said Udinese owner Giampaolo Pozzo.
"From then on we will not speak of the player's future.
"We have the preliminary of the Champions League to focus on and our coach has to know which players he will have available.
"I think that there is a 95 per cent chance that Inler will remain with us and it doesn't disappoint me because he is an important player.
"But the situation with Napoli has become an infinite soap opera."
Inler, who is also reported to be a target for Juventus, joined Udinese in the summer of 2008 from FC Zurich.
He scored three goals in 33 league appearances last season to help the club finish fourth in Serie A.