Liverpool star Philippe Coutinho has been heavily linked with a move to the Nou Camp in recent weeks.
Coutinho, 25, handed in a transfer request earlier this month in hope of forcing through a switch to Barca.
The playmaker has been tipped to replace Neymar following the winger's world-record move to Paris St-Germain.
And according to Spanish transfer outlet Don Balon, Liverpool want Sergi Roberto or Ivan Rakitic in a swap deal involving Coutinho.
However, Messi has other ideas.
The Barca talisman has told the club they cannot sell Roberto or Rakitic to Liverpool.
Don Balon add that Messi is happy to get rid of Arda Turan, Andre Gomes or Paco Alcacer in a deal that lands Coutinho.