Turkey’s recent decision to end a long-standing tax exemption on fuel for Iranian transit trucks has triggered a major backlog at the Bazargan border crossing and left some 300 trucks stranded daily in harsh winter conditions.

The move, enforced on December 29, has provoked frustration and uncertainty among Iranian hauliers and officials alike, while highlighting broader regional tensions and sparking calls for an alternative corridor to Europe.

Under the revised Turkish rules, Iranian truckers are now obliged to pay a hefty levy equivalent to 155% of the special consumption tax, based on the maximum capacity of their fuel tanks. In practice, this translates into a demand of around TRY27 per litre, which can amount to some IRR60mn-80mn (about $1,000) for a single fuel tank. This obligation applies whether the tank is full or empty, causing an outcry among Iranian operators who rely heavily on Turkey as a gateway to European markets.

The fallout from this change has been immediate. Long queues of Iranian trucks, reportedly waiting up to 10 days at the Bazargan border, have formed in sub-zero temperatures with limited access to amenities. Many drivers fear that the enduring stalemate will undermine Iran’s international trade, as a significant portion of Iranian exports destined for Europe transit through Turkish territory.

Iranian officials have not stood idle. In a reciprocal measure, Tehran ceased supplying fuel to Turkish trucks as of early January, sparking protests from Turkish drivers suddenly confronted with unexpected costs and delays.

Negotiating teams from Iran, including delegates from the Ministry of Roads and the Anti-Contraband Task Force, have travelled to Ankara seeking a resolution. However, Turkey has maintained that rescinding the measure requires assent at the presidential level, leaving little room for compromise in the short term.

The dispute has its roots in Iran’s own “full tank” policy, introduced several months ago. Aimed at curbing fuel smuggling prompted by Iran’s cheaper domestic fuel prices, it imposes costs on Turkish lorries crossing into Iran. In retaliation, Turkish authorities scrapped the reciprocal tax exemption that had been honoured for years under bilateral protocols.

Observers also point to geopolitical developments in Syria and the Caucasus, suggesting that these regional tensions may have indirectly influenced Ankara’s hard line.

Trade analysts also warn of potential disruption to Iran’s relations with the European Union, which rely substantially on smooth trucking routes across Turkey. A senior figure at the Iranian Chamber of Commerce, Fatemeh Ghanbarpour, said that this mutual taxation system was originally designed to prevent unfair competition arising from different fuel prices. She noted that Iran first introduced a plan in 2017 to charge foreign truckers a price difference on fuel – though it was never fully enforced – making today’s standoff seem like a belated escalation of old frictions.

Industry experts see the crisis as a call to action for Iran to diversify its regional trade routes and reduce reliance on Turkish transit corridors. One proposed alternative is the Persian Gulf–Black Sea transport corridor, initiated in 2016 with the involvement of India, Armenia and several other regional players. This route would connect southern Iran to ports in Azerbaijan and Armenia, and then link to Georgia’s Black Sea harbours before reaching Bulgaria and the wider European Union. Such an initiative, proponents say, would mitigate the strategic risks of overreliance on a single pathway through Turkey.

For now, however, the fate of hundreds of stranded truckers underscores the urgent need for high-level diplomacy. Without a swift resolution, the fallout could further jeopardise bilateral ties just as both countries had pledged to boost their annual trade to $30bn within five years at the 29th Joint Economic Commission meeting. The dispute threatens to damage regional connectivity at a time when Turkey is itself aiming to portray a robust role as a trade bridge between East and West.