Ukrainian drones attacked the Sheskharis oil terminal at the Black Sea port of Novorossiysk in Russia’s Krasnodar region over Sunday night, according to online channels monitoring the war. Footage posted online claimed to show a large fire at the port. Strikes on oil facilities in other regions were also reported. Russia’s military said early on Monday that air defence units downed 148 Ukrainian drones over a three-hour period and nearly half a million households were blacked out by air attacks. On Sunday evening drones killed one person in Russia’s border region of Belgorod and hit an apartment building in Russia’s Novorossiysk, Russian authorities claimed.

It came as the Institute for the Study of War assessed that Ukraine has stepped up its attacks on Russia’s oil infrastructure over the past two weeks, “focusing on the Russian Baltic Sea port and oil infrastructure in Leningrad oblast critical to Russian oil exports”. A claimed strike on Primorsk overnight on 4-5 April was the third against the port within the last two weeks, said the ISW. “The Ukrainian general staff reported on April 5 that Ukrainian forces also struck the Lukoil-Nizhegorodnefteorgsintez refinery in Kstovo, Nizhny Novgorod oblast (roughly 1,000km from Primorsk) overnight, starting a fire.” Geolocated footage showed Russian air defences responding, while fires showed up on Nasa’s Firms global satellite fire monitoring system and the oblast governor acknowledged the attacks and damage to oil company facilities, said the ISW.

Russian military bloggers noted the damage the strikes have inflicted on Russia’s oil export capacity will be “costly and time-consuming to repair”, while damaged or lost Russian ships would be difficult to replace, the ISW continued. “Russian milbloggers have previously complained about the Russian inability to repair damaged facilities due to parts sanctions and Russian air defence failures.”

In Crimea, part of Ukraine occupied by Russia since 2014, the governor of the port of Sevastopol said his city had come under four drone attacks throughout Sunday. Seven drones were downed in the latest wave. In Russian-occupied Donetsk region in eastern Ukraine, the head of the Russia-installed government, Andrei Chertkov, said repair crews had restored power to two major cities, Donetsk and Makiivka, after Ukrainian attacks. Power outages were also reported in Russian-held areas of the Zaporizhzhia region.

A cargo ship carrying wheat sank in the Sea of Azov after coming under attack from Ukrainian drones, a Russia-installed official claimed on Sunday, adding that one person was dead and two missing. Vladimir Saldo, Moscow-installed leader of the Russian-controlled parts of Ukraine’s Kherson region, said the attack occurred on Friday and the crew who abandoned ship only reached the shore on Sunday. Ukraine denies going after such targets unless there is a valid military objective.

Ukraine and Syria pledged greater security cooperation in talks on Sunday, Volodymyr Zelenskyy said. The Ukrainian president was continuing his tour of Middle East countries and met with his Syrian counterpart, Ahmed al-Sharaa, in Damascus.

Zelenskyy expressed concern that a prolonged US-Israeli war on Iran could further erode America’s support for Ukraine as Washington’s global priorities shift and Kyiv faces reduced deliveries of critically needed Patriot air defence missiles. Ukraine desperately needed more Patriots to help it counter Russia’s daily barrages, Zelenskyy said, speaking to the Associated Press in an exclusive interview in Istanbul. “We have to recognise that we are not the priority for today,” Zelenskyy said. “That’s why I am afraid a long [Iran] war will give us less support.”

Zelenskyy said Russia draws economic benefits from the Iran war, citing the limited easing of American sanctions on Russian oil. “Russia gets additional money because of this, so yes, they have benefits,” he said. Surging oil prices driven by Iran’s closure of the strait of Hormuz are undermining that strategy by boosting the Kremlin’s oil revenues and strengthening Moscow’s capacity to sustain its war effort. Ukraine has countered by stepping up attacks against Russian oil production and export infrastructure.

Zelenskyy said Ukraine was ready to share with Gulf Arab countries targeted by Iran its experience and technology, including interceptor drones and sea drones, which Ukraine produces with funding from Americans and its European partners. In return, these countries could help Ukraine “with anti-ballistic missiles”, Zelenskyy said. Ukraine’s president has also positioned Ukraine as a potential partner in safeguarding global trade routes, offering assistance in reopening the strait of Hormuz by sharing Ukraine’s experiences securing maritime corridors in the Black Sea.