According to a note published on the organisation's official website, Martínez's choices will be announced at 1pm, at Cidade do Futebol, in Oeiras.
The final list will have a total of 26 players, after, last week, UEFA authorised the inclusion of three more places to the initial 23.
At Euro2024, Portugal will compete in Group F together with the Czech Republic (on June 18 in Leipzig), Turkey (22 in Dortmund) and Georgia (26 in Gelsenkirchen).
Before leaving for German soil, the national team will play three preparatory games against Finland (June 4th, at the José Alvalade Stadium), Croatia (June 8th, at the National Stadium), and the Republic of Ireland (June 11th, in Aveiro).
Euro2024 will run from June 14th to July 14th.