It is said that Neymar jr decided to leave Barcelona following talks on holiday near Rio de Janeiro in early July, before he joined the club’s pre-season tour of the United States.
He is expected to arrive in the French capital by Friday at the latest to complete his move.
It is understood the total value of the deal is worth nearly £450m (€500m), which includes wages, bonuses and a buyout clause of £198m (€222m). Neymar has been offered a basic salary of £26.8m-a-year (€30m) after tax, around £515,000-a-week.
Barcelona confirmed the buyout clause will have to be “deposited in its entirety”.
Sky Sports News has been told that a key meeting took place in Brazil earlier last month involving Neymar, his father and super-agent Pini Zahavi, who has brokered the deal.
Zahavi has known Neymar since the age of 17 and has become one of his closest advisors.
A source in Spain close to Neymar has told Sky Sports News: “Since he decided to leave, Neymar has had to deal with huge pressure to stay at Barcelona. His teammates wanted him to stay but his decision was made.”
The source added that Neymar had been “close” to joining Manchester United in last summer’s transfer market but chose PSG after a further season at Barcelona.
Neymar is expected to join five Brazilian international teammates at PSG, including Dani Alves and Thiago Silva.
The source said: “People will say this has been driven by money, but he wants to become the leader at the club. He wants to be independent, and wants to win the Ballon d’Or. He believes he can do that in Paris.”
La Liga president Javier Tebas has threatened to block the transfer but it’s understood PSG officials remain “very confident” there will be no issues with the buyout clause.
PSG has yet to confirm whether an agreement has been reached.