The debate over euthanasia has become a prominent issue in the Spanish general election campaign after a 70-year-old man was arrested for helping his terminally-ill wife to end her life.

Ángel Hernández spent Thursday night, his first without María José Carrasco, in a Madrid police cell after confessing to administering a lethal drug dose to the long-term multiple sclerosis sufferer, who was 61.

The widower has since appeared in court and been granted release subject to further enquiries, but not without rekindling a controversy about the right to die in the traditionally Catholic country.

“The police told me ‘it’s the law’, but they would have done the same thing themselves. Yes, it’s the law, but it is wrong and it should have been resolved a long time ago,” Mr Hernández told El País newspaper.

“I could have done it secretly,” he added. “I argued about that with my wife, who was a legal secretary and knew what could happen to me. But I convinced her that it was important for this to come out, not for her anymore, but for the people who are still left behind.”

Spanish prime minister Pedro Sánchez promised to legalise euthanasia if he wins a parliamentary majority on 28th April and blamed centre-right party Ciudadanos (Citizens) and right-wing People’s Party (PP) for blocking a bill aimed at legislating for the right to die.