A column of vehicles carrying heat insulators for the Bushehr nuclear power plant, which the Russian contractor, Atomstroyexport, is building in the southwest of the Islamic Republic, was stopped at the border between Azerbaijan and Iran in late March.
"The Russian side is seeking to solve the problem as soon as possible within its competence. On our part, we have asked Azerbaijan's ambassador in Tehran to take measures for the delivery of the consignment to Iran," Iranian Foreign Ministry spokesman Mohammad Ali Hosseini said.
The Iranian diplomat said the shipment of the nuclear power equipment complied with international law and there was no ban regarding the consignment.
Azeri customs officials earlier said the cargo needed a special permit, which the Russian contractor had failed to supply.
Iran is currently under three sets of UN sanctions over its uranium program. The latest resolution against Iran froze accounts of certain Iranian companies and banks, and introduced inspections for goods leaving and entering the Islamic Republic.
Russia delivered its final and eighth fuel shipment to Bushehr on January 28. Russia has supplied a total of 82 metric tons of low-enriched uranium to the light-water nuclear power plant. Iran hopes its first nuclear power plant will be launched in October.