GENEVA, Switzerland - The Swiss on Wednesday handed a large stone-carved head back to Peru, where it was sculpted around 2,500 years ago by one of the country's earliest civilisations, the culture office said.

The monolithic sculpture, which weighs almost 200 kilogrammes (440 pounds), was brought into Switzerland by truck in 2016 from Germany at the request of a German art dealer.

Switzerland's Federal Office of Culture (FOC) said in a statement that the sculpture had not been properly declared as a cultural property. It was later confiscated as there was "substantiated suspicion" it had been illegally taken from Peru.

FOC head Carine Bachmann presented the decorative stone sculpture to Peruvian ambassador Luis Alberto Castro Joo at the Basel-Weil am Rhein customs office, where the piece was discovered seven years ago.

After it was discovered, FOC specialists reviewed the piece and determined that the "2,500-year-old stone head from the pre-Hispanic Chavin culture (circa 1200 to 550 BC) originates in what is now Peru," Wednesday's statement said.

"That makes it a significant piece of cultural property that should have been declared as such when it was imported."

Peru is heavily affected by the plundering and destruction of archaeological sites.

And pre-Columbian pieces like the stone head returned Wednesday are among Peru's most endangered categories of cultural property, the FOC said.

Switzerland and Peru are both signatories of a 1970 UNESCO convention banning the illegal import and export of cultural property.

The two countries also signed a bilateral deal in 2016 to strengthen their cooperation on the issue.

"This restitution underlines the shared commitment of Switzerland and Peru to combating the illegal transfer of cultural property," the FOC said.