Spanish Prime Minister Pedro Sánchez apologized for the corruption within his Socialist Party on Thursday, hours after a leading member of his political organization was implicated in a kickback scandal.

“I appear here to apologize to the citizens and supporters of the Spanish Socialist Workers’ Party,” Sánchez said in a televised press conference at the party’s headquarters in Madrid.

The extraordinary public apology came hours after the Spanish press revealed the Civil Guard’s Central Operative Unit (UCO) has evidence connecting the Socialist Party’s third-highest ranking member, Santos Cerdán, with the reception of kickbacks.

The UCO’s investigation suggests Cerdan colluded with former Transport Minister José Luis Abalos and his former adviser, Koldo García, to collect illegal commissions linked to public works projects.

Sánchez said he was “profoundly incensed and deeply saddened” by the revelations, because he has “always believed in ‘clean’ politics and with democratic regeneration, as well as in the fight against corruption.”

The prime minister said that would completely restructure the top structure of his party and order an independent audit of its finances.

Despite calls for his resignation from opposition parties, Sánchez said he would not resign or call snap elections because he felt an obligation to defend “that a political project in which millions believe and depend,” and which he did not want to see scuttled “by the conduct of a few individuals.”

“I apologize,” he added. “And I promise that although my feeling of deception is huge, my response to these developments will be decisive.”