Spain's lower house on Thursday passed changes to a contentious sexual violence law, widening a rift within the ruling coalition as the Socialists and their hard-left partner Unidas Podemos (UP) split into opposite camps during the vote.
The law, known as "Only Yes is Yes" and the flagship policy of the UP-led equality ministry, was approved in August and touted as a milestone for women's' rights as it focused on the concept of consent.
But while it was meant to requalify sexual abuse cases where victims did not resist out of fear into a more serious crime, a loophole in the law's sentencing guidelines has been used by hundreds of convicted rapists to reduce their prison terms or win early release, provoking a public outcry.
Prime Minister Pedro Sanchez has apologised to victims of sexual abuse over the law's "undesired effects" and vowed to fix it.
Sex crimes now carry a lower minimum sentence as a result of merging the formerly distinct felonies of sexual abuse and aggression, but the approved changes reintroduce the distinction - depending on whether there is evidence of physical violence - when it comes to setting minimum jail terms.
The Socialists had agreed on the amendments with the main opposition People's Party, angering left-wing parties that usually vote in line with the government.
Socialist deputy Andrea Fernandez acknowledged the deal with the PP left a "bittersweet sensation" but defended the need for the "technical reform" that was passed by 233-59 votes, with four abstentions, and is now headed to the upper house for ratification.
UP argues the changes put the onus back on victims, who have to prove they suffered vaginal injuries, instead of focusing solely on their consent.
Equality Minister Irene Montero said they represented a "severe setback to women's rights", adding it was "a sad day, the toughest day I've lived through as minister".
(Reporting by David Latona; Editing by Andrei Khalip and Nick Macfie)