Tehran is too weak to fight for the region today. It still intends to stop the Trump Route and to hold the Baku-Tbilisi-Ceyhan pipeline at risk.

Many have assumed that the war with Iran settled the question of Iran’s influence in the South Caucasus. A regime under naval blockade, with its oil exports near zero and its military industry in ruins, cannot afford a second front against the United States on its northern border. Tehran’s own statements suggest otherwise. 

Two interests now outrank everything else in Iran’s approach to the region: stopping the Trump Route for International Peace and Prosperity (TRIPP), the US-developed transit link through southern Armenia, and keeping the Baku-Tbilisi-Ceyhan (BTC) oil pipeline within reach as a lever against Israel and Europe. Iran treats Armenia and Azerbaijan very differently, but its quarrel with both now runs through increased engagement with the United States. 

The clearest statement came on November 5 from Ali Akbar Velayati, the Iranian supreme leader’s senior advisor on international affairs. A week after Armenia’s parliament ratified its TRIPP framework agreement with Washington by a vote of 63 to 32, Velayati wrote in the Tehran daily Ettelaat that he had given the Armenian ambassador “the final word”: “if Trump and his allies want to cross this Iranian red line, we will break their legs.” He called the ratification futile, said Iran considers itself responsible for the region’s security “with or without Russia,” and reminded readers that since the time of Cyrus the Great, the Caucasus as far as Derbent and Dagestan has served as Iran’s security buffer. 

Velayati has opposed the route from the start. Days after President Donald Trump hosted Azerbaijani President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan at the White House in August 2025, he told Tasnim that the corridor would become “a graveyard for Trump’s mercenaries.” In December, he met Armenia’s ambassador to say Iran was categorically opposed. He has now repeated the threat after a war that cost Iran its air defenses and much of its missile industry, under a blockade that has choked its revenue, and after Armenia’s legislature voted the project forward. 

His words carry more weight than those of other Iranian officials. Velayati served as foreign minister from 1981 to 1997 and has advised the supreme leader on foreign policy ever since, first Ali Khamenei and now his son Mojtaba. Iran’s Foreign Ministry and its ambassador in Yerevan, Khalil Shirgholami, have sounded more accommodating, distinguishing TRIPP from the “Zangezur corridor” Iran long opposed and saying Tehran has no reason to object absent a foreign military presence. 

On November 9, Foreign Ministry spokesman Esmaeil Baghaei said Tehran had been “assured that no US military forces will be stationed in Armenia,” while warning that the project “should not lead to changes in the geopolitical situation of the region” and that Iran is monitoring it “very closely.” Armenian officials say they take their cues from the ministry. In the Islamic Republic, however, the ministry executes a policy set in the leader’s office, and Velayati speaks for that office.

The past two years have brought American engagement with Armenia and Azerbaijan on a scale neither country has seen since independence. Russia’s war in Ukraine and Azerbaijan’s recovery of Karabakh in 2023 made it possible, removing both Moscow’s leverage and the conflict it had used to keep the two countries dependent. Iran’s foreign policy is centered on the Middle East. Still, Tehran has always regarded the South Caucasus as part of its sphere, and many Iranians see it as lost imperial territory.

Under the 1828 Treaty of Turkmenchay, signed after Russian armies had overrun the region, Qajar Persia ceded the khanates of Erivan and Nakhchivan and accepted the Aras River as its northern border. The treaty remains a staple of Iranian school textbooks, and “Turkmenchay” is a byword in Iranian political speech for humiliating capitulation to a foreign power. TRIPP would run along the very stretch of the Aras that Turkmenchay made a border, under an American flag.  

The war has raised the region’s value to Tehran. Unable to contest the US Navy at sea, figures close to Iran’s security establishment have begun describing the Caucasus as a chokepoint of their own, as my Turan Research Center colleagues Hussain Ehsani and Bako Kheladze have documented. On October 22, Caucasus specialist Ahmad Kazemi called the region a potential “Strait of Hormuz 2.0” on Iranian television. Commentator Ehsan Movahedian has claimed that fuel refined from BTC crude powered the Israeli aircraft that struck Iran.

Another analyst, Vahid Khazab, argued that strikes on Azerbaijan and the wider Caucasus could “shake confidence in global energy markets.” In June, the Revolutionary Guard-affiliated Tasnim news agency presented the Caucasus crude routes serving Israel as a card Tehran had yet to play. 

The target is well chosen. Azerbaijan supplied 46.4 percent of Israel’s crude imports in 2025, nearly all of it loaded at Ceyhan. Italy took 57.7 percent of Azerbaijan’s crude exports in the first eight months of this year. Kazakhstan, whose main export pipeline to Russia’s Black Sea coast has been repeatedly hit by drones, is shifting more of its barrels to BTC. The pipeline carries a small fraction of the oil that once moved through Hormuz. Still, a single strike would hit Israel, southern Europe and Central Asia’s westward route at once, at a fraction of the cost of challenging American warships.

Tehran has already rehearsed the idea. In early March, an adviser to an Islamic Revolutionary Guard Corps (IRGC) commander threatened “enemy oil lines,” and Azerbaijan’s State Security Service said it had broken up an IRGC plot against the pipeline. On March 5, drones launched from Iran struck the airport in Azerbaijan’s Nakhchivan exclave. The senior diplomat Kazem Gharibabadi explained that Iran does not target its neighbors unless American or Israeli bases on their soil are used against it, a standard that will justify almost anything once Tehran decides that TRIPP is an American base.

Iran’s posture toward the two countries reflects old calculations. Like Russia, Iran profited from the Armenian-Azerbaijani conflict after 1991 and chose Armenia’s side. With Turkey and Azerbaijan sealing Armenia’s other borders, the Iranian frontier became Yerevan’s lifeline, and Iranian trucks supplied Karabakh for years over Baku’s protests.

The motive was fear of Azerbaijan. Ethnic Azerbaijanis account for up to a third of Iran’s population, and Tehran has long worried that a strong, independent Azerbaijan would stir separatism among them. Baku’s partnerships with Israel, which supplies much of its arsenal and buys much of its oil, and with Turkey, its treaty ally, only deepened that suspicion.

Tehran’s hostility toward Yerevan is the newer development. Velayati accused Pashinyan of aligning Armenia with the West, deepening its enmity with Azerbaijan, and leaving it with “shaky and unpredictable” relations across the region; he also derided the “baseless and ill-considered” decision to rename the Zangezur corridor the Trump Route.

Yadollah Javani, the Revolutionary Guard’s political deputy, went further in August 2025. In a statement titled “Aliyev and Pashinyan on Zelensky’s Road to Misery,” he compared both leaders to Ukrainian President Volodymyr Zelensky, who, in Tehran’s telling, invited hostile foreign forces into a neighbor’s security zone and brought catastrophe on his own country, and warned that they would “pay dearly.” For 30 years, Iran treated Armenia as its partner against Baku. It now places Pashinyan alongside Aliyev.

Iran cannot fight for the South Caucasus today, but it does not need to. A pipeline can be put out of action by a single successful strike, and Armenia’s constitutional referendum, on which the peace treaty depends, can be swung by enough fear of Iranian retaliation in Syunik. Washington should take Velayati at his word. That means extending air and drone defenses to BTC’s terminal at Sangachal, its Georgian segment and Ceyhan, and stating publicly, together with Ankara, that an attack on the corridor will be treated as an attack on Western energy security. 

It also means moving TRIPP from paper to construction quickly while saying plainly and often that the route carries no foreign troops and remains under Armenian control. Tehran has resented the border drawn at Turkmenchay for two centuries, and it will contest the American presence along it as soon as it recovers the means. The time to secure the route and the pipeline is while Iran remains too weak to stop either.

About the Author: Joseph Epstein

Joseph Epstein is the director of the Turan Research Center, a senior fellow at the Yorktown Institute, an expert at the N7 Foundation, and a research fellow at the Begin Sadat Center for Strategic Studies at Bar Ilan University. He also sits on the advisory board of the Alekain Foundation, a nonprofit dedicated to providing education to women and girls in Taliban-controlled Afghanistan. He specializes in Eurasia and the Middle East, and his work has been featured in various outlets such as Newsweek, The Wall Street Journal, The Hill, the Atlantic Council, Novaya Gazeta, RFE/RL, Foreign Policy, and others.

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