Spain is again wrestling with the issue of euthanasia after a man was arrested for allegedly helping his seriously ill wife to die.

Ángel Fernández, 70, is reported to have confessed to assisting in the death of María José Carrasco, 61, who was diagnosed with multiple sclerosis 30 years ago. He was arrested in Madrid on Wednesday and released on Thursday night pending further inquiries.

Fernández recorded a video alongside his wife in which he asked her: “Are you still thinking that you want to kill yourself?”

Carrasco replied that she was and did not want to wait any longer. She said she understood there was no one else but him who could help her die.

Fernández said to his wife that she had asked him to help her die “many times – more than you needed to”, and said he had hoped the Spanish government’s proposed euthanasia law would be passed before he had to act.

“Today is April 2, 2019,” he said. “Do you want to go ahead and kill yourself?” Carrasco said she did, and her husband asked if she wanted to do it the following day. She said yes.

“Well then, there’s nothing more to talk about,” he said. Carrasco said: “The sooner the better.”

Fernández’s lawyer, Olatz Alberdi, said her client had confessed to helping his wife to die. “He’s always said that he wasn’t going to hide what he was doing. He wanted to get the issue out into the open,” Alberdi said.

In June last year Spain’s socialist government proposed a bill to make euthanasia legal, but the move has been opposed by the conservative People’s party (PP).

On Thursday the prime minister, Pedro Sánchez, accused the PP and the centre-right Citizens party of thwarting efforts to legalise assisted suicide and vowed to press on if returned to power in the general election at the end of the month.

“I’m overcome by María José’s case,” he wrote on Twitter. “This should have been avoided. The PP and Citizens have blocked [our] parliamentary initiative to regulate euthanasia on no fewer than 19 occasions. My commitment is firm: if I have a parliamentary majority, this right will be recognised.”

The Citizens party general secretary, José Manuel Villegas, said the party was in favour of the proposed law in general but would prefer that another law it had proposed on palliative care was approved first.

“We all need to engage in some self-criticism, but we’re not responsible for this not getting passed,” he said. “This case shows exactly why we need this regulation.”

The PP said it remained opposed to euthanasia.

Luis Argüello, the secretary general of the Spanish Bishops’ Conference, said he did not think euthanasia was a solution. “I don’t think that people should go to prison, but I do believe in the radical defence of life,” he said. “Death shouldn’t be a way of solving problems.”

Argüello offered his condolences to the family at what he called a “dramatic and exceptional time”.

The group Right to Die with Dignity said there was a gulf between the Spanish people and their laws on the issue of assisted suicide. “More than 80% of the population are in favour of decriminalising euthanasia and assisted suicide. Yet article 143 of the penal code still punishes them with prison sentences,” it said.

If Sánchez is re-elected and his legislation is approved, Spain would become the fourth country in Europe to legalise euthanasia, after Belgium, Luxembourg and the Netherlands. Switzerland allows assisted suicide.

AFP contributed to this report