The letter was delivered to César Rico, president of the Provincial Council of Burgos, on Saturday, on the occasion of the Provincial Day held in Briviesca, by the mayors of Treviño and La Puebla de Arganzón. In this sense, they have asked him to "recognize, recognize and defend" the majority will of the Treviñeses and to contribute to "a just, democratic and lasting solution for the future of the municipalities of Treviño and La Puebla de Arganzón: the integration of the enclave in the administrative organization of the Historical Territory of Álava".

The mayor of La Puebla de Arganzón, Pablo Ortiz de Latierro, and the mayor of Treviño, Enrique Barbadillo, have warned that their objective is "to channel the legitimate will of our citizens and favor the excellent development of our region", so their government action will have as "priority the resolution of the secular issue of the Treviño enclave".