Adults embarking on sexual relationships with those under 15 would be liable to be arrested for the crime of child abuse, under the new proposal.
Sources close to the ruling Popular Party were quoted in Spain’s Huffington Post as saying that the introduction of the proposed measure depends on the approval of the ministries of health and justice.
The issue will be debated in the Spanish parliament in the next few days.
The debate over the age of consent and age of marriage has been raging in Spain for some time.
Spain remains one of Europe's most permissive countries regarding teenage matrimony and consensual sex. The country’s age of consent, 13, is the lowest in Europe after the Vatican’s 12.
But the 2012 murder of a 13-year-old girl by her 39-year-old lover in the village of El Salobral (Albacete) sparked a debate over the age of consent.
The victim's parents had already alerted police of the couple’s age gap but officers were unable to intervene because their relationship was not illegal at that stage.
While Spain has one of the lowest ages of consent, it is far from being the only country in Europe to grapple with what age should be the legal minimum for consensual sex.
In Sweden, where the age of consent is 15, uncertainties over how to interpret the law have led to young Swedish teens engaging in consensual sex being dragged into court.
In 2011, a 15-year-old boy was convicted for having sex with his 13-year-old girlfriend, even though there was only an 18-month age difference between the two.
In a disturbing case from Italy, a 60-year-old paedophile was let off for having sex with an 11-year-old girl because the court had failed to take into account the girl’s “amourous feelings” towards the man.
In Norway, meanwhile, a Catholic priest in court for having sex with a 15-year-old girl claimed he did not know she was under age: the legal age of consent in his home country of Germany is 14.
In 2013, the Spanish government raised the country’s marriage age from 14 to 16.