US citizens investing in Uruguay

Hi,


I've been to the bank Itaú Uruguay asking about investing in Las Letras de Regulación Monetaria, and I have been told that I cannot invest because I am a US citizen. They said it had something to do with the IRS.


However, I have legal residency in Uruguay, with a cédula de identidad, work here and pay my taxes here.


Is there some way I can invest the Uruguayan pesos that I earn in Uruguay at a decent amount of interest with a financial institution in Uruguay?