Ukraine has struck a Russian tanker in the Mediterranean Sea for the first time, a Kyiv intelligence source has said.
The ship, called the Qendil, suffered "critical damage" in the attack, according to a member of the SBU, Ukraine's internal security agency.
The tanker is said to be part of Russia's so-called "shadow fleet" - a group of ageing vessels that Kyiv alleges helps Moscow exports large quantities of crude oil despite Western sanctions.
The SBU source said Ukrainian drones hit the ship in neutral waters more than 2,000 kilometres (1,243 miles) from Ukraine.
They said: "Russia used this tanker to circumvent sanctions and earn money that went to the war against Ukraine.
"Therefore, from the point of view of international law and the laws and customs of war, this is an absolutely legitimate target for the SBU.
"The enemy must understand that Ukraine will not stop and will strike it anywhere in the world, wherever it may be."
The vessel was empty at the time of the attack, the Ukrainian source added.
Speaking during a live TV event, Vladimir Putin, the Russian president, claimed the attack would not disrupt supplies, but vowed that Russia would retaliate nonetheless.
He added that Russia regularly responded with "much stronger strikes" against Ukraine.
Putin also warned against any threat to blockade Russia's coastal exclave Kaliningrad, which he said would "just lead to unseen escalation of the conflict" and could trigger a "large-scale international conflict".
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Sky military analyst Michael Clarke said Ukraine's claim about causing significant damage to the ship was "probably true".
He added: "The Ukrainians obviously feel that they can legitimise this sort of operation."
The attack comes after the European Union announced it would provide a €90bn (£79bn) interest-free loan to Ukraine.
Oleksandr Merezhko, the chairman of the foreign affairs committee in the Ukrainian parliament, told Sky News that the money would "tremendously enhance" Kyiv's defensive capabilities.
However, he said the International Monetary Fund estimated that Ukraine needed $137bn to "keep running".
"The aggressor should be punished", Mr Merezhko added, as he argued that frozen Russian assets in Europe should be used to help fund his country's defence.
He vowed that Ukraine would "continue to fight" for the move, adding that it was "a matter of justice".
(c) Sky News 2025: Ukraine 'hits Russian tanker in Mediterranean Sea for first time'
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