The trio formed one of the world's best attacks for three seasons at Barca before Neymar moved to the Ligue 1 giants in 2017.
Neymar has been linked with a return to Camp Nou and Messi revealed he was still in contact with the Brazil forward.
"I have a group on WhatsApp where we are – Suarez, Neymar and me," he told Fox Sports Argentina on Friday.
"Neymar is a phenomenon and yes, we continue to talk. The name of the group has something to do with South America … 'The Three Sudacas' or something like that."
Messi is preparing to potentially face Uruguayan Suarez and Brazilian Neymar with Argentina during the Copa America.
But the Barcelona star is still unhappy about the way his club's Champions League campaign ended with a semi-final loss to Liverpool, who claimed a 4-0 second-leg win at Anfield.
"It was a disgrace what happened at Liverpool. We made silly mistakes," Messi said.
Messi, however, refused to blame under-fire Barcelona manager Ernesto Valverde for his side's defeat.
"Until this game we had a spectacular season and in the Liverpool game the manager had no fault.
"He wasn't the guilty one. Liverpool overcame us in attitude. We made stupid mistakes."
The 31-year-old also suggested that his side were mentally scarred by Roma's similar three-goal comeback against them in last year's Champions League, and were unable to prevent the same thing happening again at Anfield.
"I never imagined that we could repeat the story after losing against Rome the year before. We couldn't allow ourselves to lose a game this way once again.
"They (Liverpool) were physically stronger than us and, when they scored, we remembered Rome."