Swiss officials have suspended an inquiry into money-laundering charges against former Argentine President Carlos Menem due to a lack of evidence.
Mr Menem says his accusers are politically motivated
The Swiss justice ministry said it could not find any accounts linked to Mr Menem at a Geneva bank.
Argentina had asked the Swiss to trace $10m which it said Mr Menem received as a bribe from the Iranian government.
He was accused of covering up Tehran's alleged role in the bombing of a Jewish centre in Buenos Aires in 1994.
Mr Menem, who was in office from 1989 to 1999, has consistently denied the allegations, saying they are politically motivated.
He now lives in Chile, from where the Argentine government has unsuccessfully attempted to have him extradited.
Mr Menem is also the subject of a separate investigation in Switzerland, involving allegations of illegal arms exports.
He is accused of authorising weapons sales to Ecuador and Croatia during the 1990s, at a time when both countries were under a UN embargo.