Athens has asked Switzerland to return a 480BC silver coin sold in a Zurich auction for €80,000.
The silver drachma, showing a soldier and a horse on one face and bearing a royal seal on the other, was put on sale and the Greek police were alerted by an anonymous letter in September 2009, the daily newspaper Ta Nea said.
Greece and Italy have stepped up a drive to retrieve smuggled antiques from overseas and foreign museums.