The younger brother of murdered Archbishop Oscar Romero has said he forgives his killers – but wishes they had been brought to justice.

Romero, who is to be canonised as a saint, was shot while celebrating mass at a hospital chapel on March 24, 1980.

The leader of a right-wing death squad, Major Roberto D'Aubuisson, is believed to have ordered the assassination. D'Abuisson died in 1992 and no one has been brought to account for what happened.

Romero's canonisation has been delayed because of reluctance from right-wing Salvadoran Catholics, who regarded him as too political.

Gaspar Romero, 88, told AFP that 'everyone already knows' who carried out the assassination. 'Why didn't the prosecutor's office act? That's the question. Many prosecutors have come and gone and everyone knows it – except the prosecutor's office,' he said.

A former telecommunications worker, Gaspar said his brother had told him: 'I know they are going to kill me, but I already forgive those who are going to do it.'

'So, picking up on those words, I forgive those who did it,' he said.

He said he and his brother were 'very close'. 'I felt the pain of losing a brother, and as a Salvadoran, I felt the loss that the country had of a great, good and wise man, who did not hurt anyone,' he said.

He described Oscar Romero as 'a simple man and a defender of the poor'.