Due to PSG's high asking price when it comes to selling Neymar, FC Barcelona must look to include players in a potential swap deal. This would greatly reduce the cash needed to push through a transfer.
This isn't the first time Barça have been involved in a high-profile swap deal, but they are more common in Italy than anywhere else.
Here are the most historic swap deals so far:
Zlatan Ibrahimovic to Barça, Samuel Eto'o to Inter
Barça made a sensational move to bring in the outspoken Swedish striker from Inter Milan. The Italian side were handed €45m and Samuel Eto'o to seal the transfer. Ibrahimovic didn't work out at Barça and was sold for €24m the following season.
Alexis Sánchez to Manchester United, Mkhitaryan to Arsenal
Alexis Sanchez joined Manchester United so he could work under Jose Mourinho. Arsenal wanted around €35m for the Chilean winger but instead took Henrikh Mkhitaryan in exchange. Neither player has set the world alight after their move but Mkhitaryan made the headlines recently when he didn't appear in the Europa League final due to concerns over his security.
Ashley Cole to Chelsea, William Gallas to Arsenal
Gallas had to leave Stamford Bridge. The defender had even threatened to score own goals if he was forced to remain at Chelsea. In an extraordinary move, Chelsea managed to convince Arsenal to take Gallas - and five million pounds - in exchange for Ashley Cole.
Ricardo Quaresma to Porto, Deco to Barça
The then-young Quaresma was unhappy under Frank Rijkaard and Barça sold him to Porto for €15m, with Deco coming to the Camp Nou in exchange. The midfielder helped Barça win the Champions League.
David Luiz to Chelsea, Nemanja Matic to Benfica
In 2011, David Luiz was considered one fo the most promising defenders in world football. Chelsea paid €25m for the defender and sent Nemanja Matic to Benfica. Curiously in 2014, Matic would return to Chelsea.
Fabio Cannavaro to Juventus, Fabián Carini to Inter
Cannavaro's expensive contract was causing problems at Inter and they were actively looking for options. Juventus brought him in before selling the defender two years later to Real Madrid. In that Juve-Inter deal, the men from Turin paid €10m and included Fabian Carini going to Inter
Clarence Seedorf to Milan, Francesco Coco to Inter
This was one of the rare straight swaps which didn't involve any money changing hands. Coco wanted to leave Milan and sign for Inter, whereas Seedorf wanted a greater role and Milan promised that to him.
Roberto Carlos to Real Madrid, Ivan Zamorano to Inter
Zamorano was a good goalscorer but Raul Gonzalez's rise to the first team meant his future didn't look bright at Real Madrid. A swap deal saw Zamorano move to Inter for €1m plus Roberto Carlos. The rest is history. The Brazilian became one of the greatest left backs of all time.