Valencia have reportedly postponed contract talks with in-demand left-back Jose Gaya until the end of the season.
The 19-year-old defender's breakthrough this season has led to a host of speculation surrounding his long-term future.
It was understood that the two parties were talks over an extension that would run until 2021, but discussions have stalled in recent weeks.
According to Cope, Valencia have held three separate meetings with the player's representatives, but there are disagreements over Gaya's release clause.
Real Madrid and Manchester United are both believed to be interested in the Spaniard, whose current buy-out figure stands in the region of £15m.