Local authorities in Córdoba have dealt a blow to the Catholic church’s claim of legal ownership of the Spanish city’s mosque-cathedral, declaring that “religious consecration is not the way to acquire property”.

The report, written by the city council’s secretary general, Valeriano Lavela, marks a significant intervention in a long-running row over the building, which lies on the site of a Visigothic Christian church built in the early 9th century and was given to the local bishop by Fernando III in 1236 when the city fell to Christian forces.

In 2006 the diocese of Córdoba paid €30 to register ownership of what it calls the cathedral-mosque or sometimes just the cathedral. The council’s approved name is the mosque-cathedral of Córdoba.

But the council’s report says the building does not belong to the church nor to any other organisation or individual. Lavela writes that the church’s acquisition has no legal basis and cannot confer ownership. This, he adds, is not just because the site has since 1984 been a Unesco world heritage site “of exceptional universal value” and therefore cannot be owned by anyone.

Citing Roman law, Lavela argues that the site’s true owners “are each and every citizen of the world from whatever epoch and regardless of people, nation, culture or race”.

The church has not yet responded to the report.

In 2013, hundreds of thousands of people signed a petition for the building to be managed by the local authority rather than the church in order to conserve its cultural heritage. It was in response to an inquiry into whether the city of Córdoba could ever claim ownership that the report was published.

While mass is held in the building, the local bishop has banned Muslims from praying there. In 2010 fighting broke out when a group of Muslim visitors knelt to pray.

The interior consists of hundreds of delicate red and white stone arches, giving the sense of being in a serene forest. In the 16th century a Renaissance nave was inserted which even Carlos I, the king who had commissioned the work, deplored as “having undone something that was unique in the world”.

Shortly afterwards the church planned to destroy the arches altogether but the municipal authorities intervened, threatening anyone who touched them with the death penalty.