Celtic are facing paying out a significant sum to Croatia Zagreb if they sell Jozo Simunovic.
On Friday The Sun reported that Lille were preparing a £5m bid for the defender who is under contract for two more seasons.
Celtic signed Simunovic in 2015 at the same time as Virgil van Dijk was being sold for £13m to Southampton with the Croatian side keen to ensure that they got a cut of any sell on fee.
At the time, fees of between £3m and £6m were reported for the defender who has never been able to put together a consistent run of appearances to establish himself in the way that van Dijk managed.
Celtic are believed to have had a sell on clause of 10% of the profit that Southampton made on van Dijk with Croatian site Dnevro reporting:
Soon the midfields could be changed by Josip Brekalo as well as Jozo Simunovic, and their transfer to Dinamo embedded a clause guaranteeing them the percentage of the next sale, which usually amounts to 20 to 25 percent of the next transfer. Brekala claims Benfica and offers around 20m euros, which means that Dinam would get about three million euros. Simunovic wants Lille and offers about seven million euros, and Dinamo could earn about one and a half euros.
Celtic are unlikely to reject an offer in the region of £5m for the 24-year-old but won’t do business while they are involved in the qualifying stages of the Champions League.
Christopher Jullien and Kris Ajer are likely to be Neil Lennon’s first choice pairing in central defence but after Simunovic the options appear to be Nir Bitton, Jack Hendry and Stephen Welsh.