The Dutch midfielder was seemingly on his way to the Camp Nou next season to reunite with Ronald Koeman until PSG swooped in at the last minute.
The 30-year-old revealed PSG were just quicker and were more clear about what they wanted.
"It was a difficult choice. We negotiated with Barcelona for 4 weeks, but we did not reach an agreement," the former Liverpool midfielder said, as per the Mirro.
"PSG were just quicker and their project spoke to me more. To be honest, I thought I was joining Barcelona because at the beginning they were the only interested club.
"PSG and Barcelona are both truly great clubs, and both are clubs where I would have liked to play. I wanted to make my decision before the start of the Euros and in the end I chose PSG."
Hugo Lloris (Tottenham Hotspur) – linked with AS Roma
Olivier Giroud (Chelsea) – linked with AC Milan
Jack Grealish (Aston Villa) & Harry Kane (Tottenham Hotspur) – linked with Manchester City
James Ward-Prowse (Southampton) – linked with Aston Villa
Lautaro Martinez (Inter Milan) – linked with Atletico Madrid
Kieran Trippier (Atletico Madrid) – linked with Arsenal & Manchester United
Gianluigi Donnarumma (AC Milan) – linked with Paris Saint-Germain & Juventus
Georginio Wijnaldum (Liverpool) – linked with FC Barcelona & Paris Saint-Germain
Memphis Depay (Olympique Lyonnais) – linked with FC Barcelona & Juventus
Scroll through the gallery to see some of this week's top transfer rumours