Switzerland's government has handed over a prehistoric Libyan marble sculpture believed to be more than 2,000 years old to Libya's embassy in the Swiss' capital, Bern.

The sculpture of a young woman’s head measures 19cm (seven inches) high and "dates to the period between the first century BC and first century AD", Switzerland's Federal Office of Cultural Affairs said in a statement.

"It most likely originated from the archaeological site of the ancient city of Cyrene, located in the Cyrenaica region in present-day Libya" and is "tangible evidence of Greek expansion in North Africa", the office added.

The sculpture was found in a customs warehouse in Geneva in 2013 and legally confiscated by Swiss authorities in 2016.

The office added that there "was sufficient reason to believe that it had been acquired as part of an illegal excavation", but were unable to determine how the sculpture ended up in Switzerland.

Libya and Switzerland are both party to a 1970 Unesco treaty that seeks to prevent the illegal trade of cultural property.

The office echoed previous warnings by the UN and other organisations about the widespread looting and destruction of Libya's ancient artefacts.