Senegal has recalled its ambassador to Iran, saying that Tehran had failed to provide a "satisfactory" explanation for an arms shipment seized in Nigeria.
The weapons were found hidden among building materials on a ship docked in Lagos in October.
An Iranian man and three Nigerians have been accused of attempting to import the arms and send them to The Gambia, which cut ties with Iran last month.
But there has been speculation that they were destined for south Senegal.
Despite a peace deal, a low-level separatist rebellion simmers in Casamance, a region cut off from the rest of Senegal by The Gambia.
The Iranian government has said only that the shipment belonged to a private company and was being sent to a "West African country".
"True to the need for peace and security which should guide ties between states, and deeming not satisfactory the explanations provided by the Iranian side in this affair, Senegal has decided to recall its ambassador to Iran for consultations as of today," the foreign ministry said.
Iranian Foreign Minister Monouchehr Mottaki was sacked on Monday while on an official trip to Senegal. No reasons were given.