Iran's winter gas gap puts the Tabriz–Ankara pipeline first in line

The noise is the swap offer, the signal is the gas balance

Hormuz dominated the headlines on 24 October. According to CBS, Iran's ambassador to Pakistan said the strait would reopen if the US lifted its blockade. Khaama, citing AP, reported that Tasnim, which is close to the Revolutionary Guards, said the same day that no such swap had been accepted. IMF PortWatch data compiled by Straits.live show only 4 ships transiting on 18 October, against a pre-crisis daily average of 85. Neither the offer nor the denial changed a flow of 4 ships.

The quiet variable arrived from Tehran on 25 October. According to Iran International and Gulf News, parliament speaker Mohammad Bagher Ghalibaf called for a national campaign to cut natural gas consumption by at least 10% before winter. Ghalibaf also asked for faster roll-out of a savings certificate scheme involving about 100 private companies. When the parliament speaker of a major gas producer asks for 10% savings, it signals that repairs will not be finished by winter. Talay's reading is this: the first volume Iran is likely to cut this winter is the gas flowing through the Tabriz–Ankara pipeline, whose contract expired in July.

1 · The logistical constraint and its threshold

On the oil side, the constraint sits in the fleet. AFP reports that about 12 empty Iranian tankers are waiting off Sri Lanka's port of Galle, and at least 40 sailors were brought ashore for treatment at the weekend. The US blockade stops the ships from returning home to load, and many have drifted towards Malacca and Singapore. Those 12 tankers show that even if the blockade lifts, exports will lag by however long the ships take to return to the Gulf.

On the gas side, the constraint sits in 1 pipeline. According to Iran International, the 25-year contract between BOTAŞ and Iran expired on 29 July, with a maximum annual volume of 9.6 billion cubic metres. Noonpost gives the expiry date as 31 July, so the 2 sources differ by 2 days. For about 3 months the flow has continued under a force majeure arrangement without a new contract. Türkiye imported 4.536 billion cubic metres from Iran in the first half of 2026, 34% more than a year earlier, including 883 million cubic metres in June alone.

The threshold Talay is watching is monthly Iranian flow to Türkiye falling below half of June's 883 million cubic metres. A breach would show that Iran is putting domestic demand ahead of exports, and that the cut is policy rather than a one-off fault.

2 · Security of supply and critical thresholds

According to a NIAC analysis dated 15 October, the National Iranian Gas Company said strikes on 4 processing plants had wiped out about 230 million cubic metres a day of capacity. Repairs restored roughly 100 million of that, while the remaining 130 million is still offline; the figures are official and have not been independently verified. MEES reports that Vice President Kaempenah said on 20 July the loss equalled 35% of sales gas output of about 650 million cubic metres a day. According to Iran International, Oil Minister Paknejad put the loss at 95 million cubic metres in August and said it would be restored by the end of September. The savings call on 25 October suggests that timetable has slipped.

NIAC says Iran's winter peak gas deficit was already between 200 and 250 million cubic metres a day before the war. Tehran's priority is electricity. Tavanir says the peak power deficit fell from about 20,000 megawatts in summer 2025 to about 10,000 megawatts in summer 2026. Power plants have 3.2 billion litres of liquid fuel in storage, about 25% more than a year earlier. Liquid fuels are tight as well: on 25 October Iran International published 1 video showing drivers in Karaj stopping work over a diesel shortage.

For Türkiye, the precedent is 4 years old. Data compiled by Noonpost show that when 1 compressor failure cut Iranian gas in January 2022, Türkiye asked power plants to reduce output by 40%. Iran's share of imports was then about 16%, and gas in storage stood at 3.2 billion cubic metres. In 2025, Iran supplied 8.17 billion cubic metres, a share of 13–14%.

3 · Second-round effects

The first link in the chain is Iran's domestic prioritisation. If the National Iranian Gas Company curbs industry and exports during the first cold snap, flow through the Tabriz–Ankara pipeline falls. Noonpost puts Türkiye's storage capacity at about 6.3 billion cubic metres at the end of 2025. Winter consumption approaches 230 million cubic metres a day, and LNG regasification capacity is given as 151 to 161 million cubic metres a day. Storage fill levels as of October 2026 could not be verified.

The second link is price. According to Noonpost, the Iranian contract was indexed to oil, while about 15.8 billion cubic metres of LNG contracts signed since 2024 are tied to gas benchmarks such as TTF and Henry Hub. If spot LNG replaces Iranian volumes, BOTAŞ will compete with European and Asian buyers for the same cargoes in the most expensive weeks of winter. With Brent closing at 116.72 dollars on 23 October, the old oil-indexed price was not cheap either; the price under the force majeure arrangement has not been disclosed.

The third link is the balance sheet. Expensive replacement gas raises BOTAŞ's costs, which pass either into tariffs or into the budget, while the energy import bill erodes the current account. Insurance adds pressure too. With Hormuz transits down to 4 ships on 18 October, risk on Gulf-sourced LNG cargoes remains elevated.

4 · What would disprove this reading

The thesis holds that Iran's gas deficit in the 2026–27 winter will make flows to Türkiye the first point of curtailment. It fails if monthly Iranian flow to Türkiye stays above 800 million cubic metres from November to January and the National Iranian Gas Company announces no industrial cuts; we put that path at 30%. Our base case, partial curtailment during cold snaps, carries a 50% probability. We assign 20% to flows stopping for weeks after a new strike or a harsh winter.