Venezuela has not managed to present necessary evidence to confirm the election result, says Borrell.
"Only results that are complete and verified by independent parties will be accepted and recognized", it says in the statement, where Borrell demands that votes from all electoral districts be published in their entirety.
Both the sitting President Nicolás Maduro and the opposition declared themselves winners after the election on July 28, and the unrest that has followed has so far claimed 27 lives. Nearly 200 people have been injured and around 2,400 have been arrested.
The Supreme Court in Venezuela, dominated by people loyal to Maduro, has backed the president's claim that he won the election. The government-loyal electoral authority CNE has also declared Maduro the winner, but without publishing any detailed election result.
Maduro's claim to election victory has been questioned by several Latin American countries, the USA, and the EU.
