The leadership election takes place in order to replace Alberto Garzón as coordinator after he resigned in late November 2023.

[1] Besides, the assembly is expected to clarify United Left's relation with Sumar, the electoral platform launched by Labour Minister Yolanda Díaz ahead of the 2023 Spanish general election.

Four candidates were running to replace Garzón: Sira Rego, Minister of Youth and Children and former member of the European parliament; Antonio Maíllo, former coordinator of United Left in Andalusia and former member of that region's parliament; José Antonio García Rubio, member of the party's board; and Álvaro Aguilera, coordinator of United Left in the Community of Madrid and secretary general of the branch of the Communist Party of Spain in that region.

[2] After Garzón resigned, negotiations started among the different factions in United Left to find common ground ahead of the assembly.

However, in March, Rego, who was widely regarded as Garzón's replacement as she was United Left's only minister in the government, unilaterally announced her candidacy.