Iran has vowed to strike back at Ukraine after a Ukrainian drone hit an Iranian vessel transporting military equipment to Russia across the Caspian Sea.
The attack, which took place in the early hours of Saturday, left one sailor dead and another wounded.
Tehran responded with fury, calling in Ukraine's top diplomat in Iran to deliver a sharp rebuke.
The Iranian Foreign Ministry declared the strike would not go unanswered.
With just 1,200 miles separating the two capitals, both nations possess ballistic missile arsenals capable of reaching the other's territory.
Ukrainian President Volodymyr Zelensky celebrated the operation, saying Ukraine had "achieved very strong results with long-range strikes in the Caspian Sea, including vessels used in military cargo shipments involving Iran, as well as a warship."
President Zelensky also disclosed that Russia has been conducting satellite surveillance of Gulf states and American military installations in the region since the start of July.
He said: "These images subsequently appear in Iran. There is a clear correlation between Russia's satellite imagery of these sites and Iranian strikes."
Iran has vowed to strike back at Ukraine after a drone hit an Iranian vessel transporting military equipment to Russia across the Caspian Sea
|REUTERS
The Ukrainian President pledged to pass this intelligence on to allied nations.
His revelation has stoked fears that the two defining conflicts of the current era, the war in Ukraine and the confrontation between the United States and Iran, could converge into a single, interconnected struggle.
Analysts pointed to the development as unmistakable evidence that the scope of the war is expanding beyond its original boundaries.
The Caspian Sea, the world's largest inland body of water, sits between Russian and Iranian territory and has long served as a logistics corridor linking the two states.
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Ukrainian President Volodymyr Zelensky celebrated the operation
|REUTERS
Tehran has relied on this route to ferry military hardware, including Shahed drones, northward to support Moscow's campaign against Ukraine.
Kyiv has increasingly targeted these shipments with long-range strikes.
Separately, Kyiv revealed that Moscow is preparing to intensify its troop mobilisation this autumn, with plans to recruit an additional 30,000 North Korean soldiers for a fresh winter offensive.
Despite Donald Trump warning last week that he would escalate military action, following almost a fortnight of daily exchanges after the collapse of the peace deal, no strikes were carried out over the weekend.
The attack, which took place in the early hours of Saturday, left one sailor dead and another wounded
|REUTERS
Iran reciprocated by suspending its attacks on American bases across the region.
However, an oil tanker reportedly detonated after striking a mine in the Strait of Hormuz, apparently after straying from the Tehran-sanctioned northern shipping lane into waters still laden with mines from Iran's efforts to dominate the waterway.
Whether anyone was killed or injured remains unknown.