The US boarding of an oil tanker in the Indian Ocean on Tuesday shows Washington making good on a pledge to track Iran-linked vessels anywhere in the world, an extension of its blockade of Iranian ports that increases the pressure on Tehran.
But the expansion of the area of conflict thousands of miles from the Persian Gulf could widen the gap to be overcome at any peace talks.
US Joint Chiefs chairman Gen. Dan Caine last week emphasized that Iran-linked vessels would have a hard time avoiding the global reach of the US Navy. He specifically mentioned the area overseen by US Indo-Pacific Command (INDOPACOM).
Marine tracking data showed the tanker, the M/T Tifani (International Maritime Organization ship number 9273337), which can carry 2 million barrels of crude oil, was stopped between Sri Lanka and Indonesia, more than 2,000 miles from the Persian Gulf, within the INDOPACOM area of responsibility.
It was heading toward the Strait of Malacca, having been at Iran’s Kharg Island oil terminal inside the gulf as recently as April 6, according to satellite imagery seen by CNN.
Marine traffic data showed it in the Gulf of Oman, outside the Strait of Hormuz, on April 10, traveling southeast.
On April 21, shortly after passing Sri Lanka, the tanker made an abrupt course change — first a sharp 90-degree turn to the south, then another sharp 90-degree turn back east.
Soon after, the US announced the boarding.
A CNN review of the Tifani’s movements over the past year shows it traveling frequently between the Persian Gulf and Malaysia’s Eastern Outer Port Limit (EOPL) on the eastern side of the Strait of Malacca.
The EOPL is a spot where sanctioned oil from “dark fleet” tankers is transferred to other vessels to obscure its origin and evade sanctions.
In the past year, the Tifani appeared to make several such transfers in the EOPL and Singapore Strait, according to MarineTraffic data reviewed by CNN.
A satellite image obtained by CNN showed the ship directly alongside another tanker named the Macho Queen in August 2025. CNN matched the vessels in the satellite imagery by comparing their length and visual characteristics.
Video released on social media by the US Defense Department showed troops boarding helicopters on a US Navy warship and landing on the tanker.
That warship, an expeditionary sea base, is about the size of an aircraft carrier and can support helicopters and special forces.
Its use in the boarding operation in the open waters of the Indian Ocean gives an indication of the vast resources the US Navy has to impose a blockade and enforce sanctions.
The Defense Department did not name the ship, but the USS Miguel Keith, one of five expeditionary sea base vessels in the US fleet, was recently in the area, having transited through the Malacca Strait. CNN has reached out to US Central Command and the 7th Fleet for comment.
The interception at the weekend of an Iranian cargo ship, the M/V Touska, was carried out by a guided-missile destroyer – the Navy has 74 of those – with Marines from an amphibious assault ship, basically a small aircraft carrier. The Navy has nine of those and 11 aircraft carriers, though not all ships are combat-ready at any one time.
The interdicted ships are believed to be part of the “dark fleet” that helps move Iranian oil and other commodities, including those with military applications, around the world.
“As we have made clear, we will pursue global maritime enforcement efforts to disrupt illicit networks and interdict sanctioned vessels providing material support to Iran — anywhere they operate,” the Defense Department social media post Tuesday said.
“International waters are not a refuge for sanctioned vessels,” it added.
Analysts also say the open ocean is a safer place for the US Navy to make interdictions, with fewer neutral vessels nearby and no land masses to restrict maneuverability or conceal adversaries, as may be the case in and around the Persian Gulf.
The open-sea tactic mirrors what the US did when tracking down tankers linked to Venezuela earlier this year – before eventually snatching President Nicolás Maduro in a raid.
Since the boarding of the Tifani, it has been circling in the ocean near where it stopped, according to tracking data seen by CNN.
What happens to it and the oil it carries remains to be seen.
The ship is the subject of sanctions by the US Treasury’s Office of Foreign Assets Control.
The US Justice Department in February filed a complaint to have an Iran-linked Venezuelan tanker seized by US forces – and its load of 1.8 million barrels of crude – forfeited to the US government.
After the Touska was seized on Sunday, analysts said it would be searched and its cargo checked. The ship and cargo could become property of the US government if it is eventually judged to be a “prize” of war, analysts said.
Iran previously vowed to retaliate for the “criminal” seizure of the ship, which its Foreign Ministry said Tuesday was a violation of the ceasefire that went into effect on April 8.
Iran has since refused to send a delegation to a new round of peace talks in Pakistan.
Whatever the disposition of the Tifani and the Touska, for the moment, the tactic doesn’t seem to be bringing Iran closer to the negotiating table.
For now at least, the expanding of the war zone with more far-seas interdictions seems likely to only harden Tehran’s position.
CNN’s Isaac Yee and Teele Rebane contributed to this report.
