Trump’s peace deal in the Caucasus tightens pressure on Iran

Since January 30, the U.S. Air Force has carried out approximately 35 military cargo flights to both Armenia and Azerbaijan, coinciding with escalating regional tensions related to Iran. According to FlightRadar, Armenia topped the list with 20 flights, compared to 15 flights to Azerbaijan, reflecting a notable focus on the two countries located along Iran’s northern border.

The data also indicated that more than half of these flights departed from Ramstein Air Base in Germany, the largest U.S. military air base in Europe. Most of the flights were conducted using Boeing C-17 Globemaster III military cargo aircraft, a heavy strategic airlifter used to transport military equipment and supplies, with a maximum payload of approximately 78 tons. Only four flights were recorded using three Lockheed Martin MC-130J Commando II aircraft, which are designed to support special operations missions. These aerial movements coincided with a visits by U.S. Vice President JD Vance to Azerbaijan and Armenia, during which several economic and security agreements were signed with the United States.

This visit comes at a time when US–Iranian tensions are at an all-time high signaling that the US is making the most of its assets in the region, including its recent strive for an Azerbaijani–Armenian peace plan.

That plan has immediately unsettled Armenia and Azerbaijan’s southern neighbor, Iran. Publicly, Tehran has taken care to welcome any agreement that reduces the risk of renewed conflict in the South Caucasus, arguing that stability benefits the region (Islamic Republic News Agency, August 9, 2025). Yet the ministry simultaneously warned about the “adverse effects” of foreign involvement at shared borders, with reference to US presence and the prospective role of American firms in constructing and managing the corridor. Iran’s mention of “shared borders” references the roughly 40-kilometer Iran–Armenia border, a strategic passage that Tehran views as essential to its northbound connectivity and commercial transit.

Iran’s anxiety is therefore not limited to the existence of a route to Nakhchivan, but to the governance model reportedly attached to it. If the TRIPP’s construction, security, or supervisory functions are outsourced to U.S. companies, Tehran reads this as more than an infrastructure project; it becomes a geopolitical foothold. That fear has sharpened in the aftermath of the Israeli–Iranian fighting and the U.S. strike on Iranian nuclear facilities on June 21, events that have reinforced an Iranian narrative of encirclement. Ali Akbar Velayati, an advisor to Iran’s Supreme Leader Ayatollah Ali Khamenei, has criticized the TRIPP, stating that it is a staging ground for “Trump’s mercenaries.”

Armenian officials, for their part, have attempted to neutralize Iranian concerns. During Iranian President Masoud Pezhakian’s visit to Armenia on August 19, Yerevan reportedly offered assurances that implementation of the project would not threaten the Iran–Armenia border or disrupt bilateral transit. In an interview with Saudi Arabia’s Al Arabiya channel, Azerbaijan’s President Ilham Aliyev said that “there have been a lot of rumors in some media and on some internet sites that Azerbaijan is planning to occupy Zangezur, or that Azerbaijan is planning to cut the Iranian–Armenian border. That was absolutely false.”

According to Vali Kaleji of Jamestown, Iran is focused on three matters pertaining to Azerbaijan’s route to Nakhchivan through Armenia.

First, Iran is wary of any US commercial presence running through southern Armenia near its border. Even if the TRIPP is formally a civilian transit project, U.S.-linked corridor infrastructure sitting close by will lead to increased skepticism from Tehran about surveillance, leverage, and the gradual normalization of external presence in a sensitive zone. In a best-case scenario, from Tehran’s perspective, any externally managed segment would be positioned as far from the Iran–Armenia border as geography allows.

Second, the TRIPP encompasses the Iran–Armenia north–south highway, where Iranian construction companies have interests. Iran seeks binding guarantees that trade and movement along that north–south line will not be delayed, inspected, or constrained by corridor-related arrangements.

Finally, and most fundamentally, Iran insists that any Azerbaijan–Nakhchivan route through Armenia must remain under Armenian jurisdiction. The latter does not apply when reviewing the August 8 agreement. According to the agreement, the security and supervisory responsibilities of the TRIPP are handled by U.S. companies. Tehran worries that the logic of inspection and control could spill over to adjacent transit routes, including Iran–Armenia commerce and the movement of citizens. The specter for Iran is not necessarily a declared blockade; it is the slow accumulation of discretionary constraints imposed by a third party.

These concerns are magnified by the competitive corridor politics already underway. As the TRIPP proceeds, it may diminish the relative value of Iran’s alternative: the “Aras Corridor.” The corridor is a transit route Iran and Azerbaijan agreed to develop after Azerbaijan’s September 2023 consolidation of Karabakh. It is intended to connect Azerbaijan to Nakhchivan via Iran’s East Azerbaijan province, bypassing Armenia. For Tehran, the corridor preserves a measure of leverage over east–west movement. A functioning TRIPP could sideline that leverage by providing Azerbaijan a direct route through Armenia that no longer depends on Iranian territory. At the same time, there are scenarios in which TRIPP’s negative consequences for Iran could be partially offset.

Iran’s strategic unease is inseparable from the broader geopolitical drift of the region. A durable Armenia–Azerbaijan settlement could accelerate Armenia’s normalization with Turkey and deepen Yerevan’s Western orientation. Armenia’s cooling ties with Russia and the reported withdrawal of Russian border forces from certain posts have already signaled a rebalancing. For Iran, a South Caucasus that is more Western-aligned while Azerbaijan maintains close relations with Israel represents an unfavorable strategic geometry: diminished Russian ballast, increased Western presence, and a potentially tighter security partnership network on Iran’s periphery.

This is why Tehran’s objection is often expressed in a single, blunt formulation: Iran loses not only because the corridor risks placing the United States on its northern edge, but because a corridor arrangement that compromises Armenian sovereign control could, in the worst case, sever Iran’s access to Armenia, and, by extension, routes to Georgia and onward to the Russian Caucasus. When the corridor remained closed, Iran benefited from geography: Turkey’s eastward connectivity was more dependent on transiting northern Iran, giving Tehran leverage over east–west trade. TRIPP threatens to reduce that leverage.

As this leverage diminishes, the room for the US to operate militarily, and hence “encircle” Iran, adds a new layer of pressure on the Iranian regime to yield to US conditions.