Barcelona forward Neymar wants Financial Fair Play assurances from Paris-Saint Germain before signing for the Ligue 1 giants.
The Brazil international is reportedly eager to leave Barcelona after becoming frustrated playing alongside club legend Lionel Messi, agitated at being in the Argentina international's shadow.
According to Radio Monte Carlo via AS, the delay in the deal is down to Neymar's representatives not being given assurances regarding Financial Fair Play, due to the enormity of the deal.
Neymar needs guarantees regarding certain aspects of the deal and he is eager to know whether the transfer could later be scrutinised by UEFA, with the former Santos ace eager to find out if he or PSG could be sanctioned by Europe's governing body.
PSG could be banned from European football by UEFA, a punishment which would be a major problem for Neymar, who came third in the 2015 Ballon d'Or and is seen as one of the world's top footballers.
However, there have also been reports claiming Neymar is set to stay at Barcelona after having talks with his teammates, with centre-back Gerard Pique posting an image on Instagram seemingly confirming the 25-year-old's immediate future is with the Catalan giants.
The €222m deal would make Neymar the world's most expensive player, easily surpassing the €105m Manchester United forked out for midfielder Paul Pogba last summer.
Neymar joined Barcelona in 2013 and has so far scored 105 goals in 186 appearances for Ernesto Valverde's side, winning a Champions League, two La Liga titles and three Copa del Rey trophies.