The pair played together for four seasons at Barcelona before Neymar's world record €222 million transfer to PSG in August, with the Brazilian's departure from Camp Nou accompanied by claims that he had to leave to escape Messi's shadow.
Goal's sister site Omnisport reported on October 9 that Neymar has demanded Barca be kicked out of the Champions League over a €26 million bonus dispute.
There looked to be no animosity between Neymar and Messi following the last round of World Cup qualifiers, however, with the PSG ace claiming he is happy for his former team-mate.
"I'm happy for him," Neymar told reporters after Brazil's 3-0 win over Chile.
"I'm happy to see a friend participate in such an important competition. I also have friends in the Chile team but we're men. We have to play to win every game."
Neymar provided an assist for Gabriel Jesus's first goal in the victory against Chile, playing 84 minutes of the clash as Brazil finished their qualifying campaign with 12 wins from 18 games at the top of the South American qualifying table.
Since moving to PSG, the 25-year-old has scored six goals in six Ligue 1 games as well as two Champions League goals in two appearances. He has also been named on the 30-man list of nominees for the Ballon d'Or alongside Messi and bookies favourite Cristiano Ronaldo.
Messi's wife Antonella Roccuzzo, meanwhile, also congratulated her husband, writing on Instagram: "PRIDE. As always, there was no doubting it !! You deserve it more than anyone my love!!!! Now come on and back home, we miss you so much!!!!"