Cecilia Jimenez, the 80-year-old who inadvertently ruined a 19th-century fresco of Jesus, insists she had the priest's permission to carry out the work.

"The priest knew it. He did. How could do something like that without permission? He knew it," she said, adding that nobody stopped her when they saw she was working on the art piece.

"Everybody who entered in the church could see me as I was painting so nothing on doing it secretly, nothing."

Jimenez decided to repair Ecce Homo, painted by Spanish artist Elias Garcia Martinez, after she noticed it had deteriorated.

"At first she just painted on the tunic but the problem started when she painted on the head, and that's when she destroyed this painting," said Martinez's granddaughter Teresa.

Professional restorers are expected to arrive on Monday, and face a gruelling task given the painting was done with oils directly onto the wall of the church.