Ciudadanos leader Albert Rivera embraces Madrid candidate Ignacio Aguado. SUSANA VERA / REUTERS

In the aftermath of Sunday’s regional and municipal elections, the Popular Party (PP) is now faced with having to make deals with Ciudadanos to keep control over decisive regions such as Madrid, La Rioja, Murcia and Castilla y León.

But on Monday morning, Ciudadanos leader Albert Rivera reiterated the emerging force’s non-negotiable condition for any agreement: the introduction of party primaries as a gesture of democratic regeneration.

“That condition is going to be on the table,” said Rivera, whose party has successfully made the jump from Catalan politics to the national arena this year. A strong showing on Sunday has seen it become the country’s third most-voted force after the PP and the Socialist Party (PSOE).

We are not going to support administrations that continue to govern the same old way”

Albert Rivera, Ciudadanos

Ciudadanos has managed to win a presence in 10 of the 13 regional assemblies that were up for grabs, taken control of around 50 municipalities and earned over 1,500 councilors nationwide. Its representatives will not rule in any coalition, but will seek to exert an influence from the opposition with a view to the general elections in November, where it hopes to make the leap into the central government.

The 35-year-old Rivera, whose message of change has connected with voters in a similar way to that of anti-austerity party Podemos, stressed that Ciudadanos would have a national policy based on its 10-point anti-corruption plan, which includes the item about the primaries.

“We are going to set conditions to improve the lives of Spaniards and to improve democracy,” said Rivera in an interview on TV network Telecinco. “Otherwise, they can seek support elsewhere; maybe they can try with Podemos.”

“We are not going to support administrations that continue to govern the same old way,” he continued. “We are not going to be a crutch or a sidekick to the two-party system. We have the legitimacy and authority to set conditions for changes that will benefit citizens, not parties.”

Since March, Ciudadanos has been negotiating its abstention in Andalusia, which held early regional elections but has since remained without an official premier because opposition parties have refused to support the investiture of the Socialist Susana Díaz.

“The PSOE got scared,” said Rivera about his demand that the Socialists eject Manuel Chaves from the party. Chaves, a former Andalusian premier and now a national deputy, has been ensnared by a scandal involving the misallocation of millions of euros meant for struggling businesses in the southern region. Ciudadanos’ anti-corruption measures include kicking out any politician involved in a graft case.

But while an abstention would be enough to let the Socialists rule in Andalusia, Ciudadanos will have to actively vote yes in places such as Madrid if it wants to support the PP’s Cristina Cifuentes.