A commission set up by the Spanish government has recommended that the remains of General Francisco Franco should be exhumed.
The dictator's tomb is inside a Catholic basilica, at a politically divisive civil war memorial.
The site, near Madrid, has been a rallying point for the far right.
The commission said the remains of Gen Franco - who ruled between 1936 and his death in 1975 - should be handed over to his family for reburial.
The vast site, known as the Valley of the Fallen, contains mass graves with the remains of 34,000 people from both sides killed in Spain's 1936-1939 civil war.
It features a 150m cross that can be seen from miles around.
The report says Franco's remains should be removed because he did not die in the war.
The general died of natural causes at the age of 82.
The general commissioned the giant monument, which is carved into the side of a mountain, to commemorate his victory over the Republicans in the civil war.
Until a law was passed in 2007 banning demonstrations at the site, the Valley of the Fallen had seen crowds of supporters gather on the anniversary of Franco's death in November.
The commission was set up by Spain's outgoing socialist government.
Correspondents say the centre-right Popular Party, which will take office on 22 December after winning general elections earlier this month, is less likely to support the commission's conclusions.
A commission member said the report's release had been delayed until after the election because of the site's sensitivity.
General Franco's family has previously said they would be opposed to his body being removed from the Valley of the Fallen.