The Blues have discussed a £1.25million transfer fee with Boca for the Argentine and it has been suggested that he may arrive at St Andrews on loan before that occurs.
Mouche's agent, Jose Luis Pineiro, confirmed that Birmingham were in with a good chance of acquiring the 23-year old.
"At the moment, the strongest offer from Europe is Birmingham asking to take the player on loan with the right to buy," he told calciomercatoweb.it.
"The English club are very interested. Boca are willing to sell him and if he takes a European Union passport then it would also be a good opportunity for Italian clubs.
"Parma expressed interest last summer, but I have not yet had contact with Milan. "