Russian drones hit a Chinese ship as part of strikes on civilian vessels approaching Ukraine’s Odesa ports on the Black Sea on Monday, Ukrainian authorities said. The Ukrainian navy described the Ksl Deyang as a Chinese-owned cargo ship sailed by Chinese crew under the Marshall Islands flag. The Deyang was heading to load iron ore concentrate in Ukraine’s Pivdennyi port in the Odesa region, Reuters reported, citing a source. The Ukrainian president, Volodymyr Zelenskyy, said a Russian drone hit the Chinese-owned vessel. It reportedly sailed on after the attack.

Ukraine’s seaports authority said another ship sailing under the Guinea-Bissau flag was hit, while the Odesa governor, Oleh Kiper, said separately that a Russian attack hit a Panama-flagged civilian vessel heading to Ukraine’s Chornomorsk port. No one was injured, the crew extinguished the resulting fire and the vessel continued on its way.

Ukraine has observed attempts by Russia to export grain from occupied Crimea involving US companies, Zelenskyy said. “In particular, we have recorded attempts to organise the export of grain from the temporarily occupied territory of Crimea – and, regrettably, other forms of economic exploitation of the peninsula involving entities from the United States.” Zelenskyy said Moscow was also trying to bring investment from “democratic countries” into Russia’s Arctic oil and gas projects.

Ukraine’s foreign ministry condemned tactical nuclear weapons drills in Belarus on Monday, blasting the deployment as an “unprecedented challenge” to global security. “By turning Belarus into its nuclear staging ground near Nato borders, the Kremlin is de facto legitimising the proliferation of nuclear weapons worldwide and setting a dangerous precedent for other authoritarian regimes,” the ministry said. Kyiv urged its western allies to tighten sanctions against Moscow and Minsk.

Vladimir Putin has few good options in Ukraine, Estonia’s foreign intelligence chief has said, with Moscow’s armed forces unable to advance significantly on the battlefield while western sanctions are chipping away at his resources. Kaupo Rosin told Reuters that Russia was losing more men than it was recruiting and a general mobilisation would be deeply unpopular and potentially undermine stability. “All these factors together are creating a situation where some people in Russia including in the higher levels understand that they have a big problem. Hard to say what Putin thinks about it, but I think all these factors are starting to float into his decision-making … My message is let’s push forward with [sanctions]. This is not the time to hesitate, just let’s keep going.”

Another European intelligence chief, who spoke on condition of anonymity, told Reuters that there were growing signs of pressure on Russia, but no indication for now that was changing Moscow’s calculus in the war. “It’s very difficult for me to see that they [Russia] would get rid of their objective to get the whole Donbas area … and Russia is in no hurry, basically.” The spy chief described Russian society as resilient. “It is wishful thinking that now Russia’s leadership is in some way eroding, or Putin is somehow challenged [domestically].”

Democratic senators blasted an “indefensible gift” to Putin after the Trump administration waived sanctions on Russian oil for another 30 days. “Every additional dollar the Kremlin earns from this licence helps Putin finance his illegal war against Ukraine and kill innocent Ukrainians,” said a statement from Jeanne Shaheen of New Hampshire and Elizabeth Warren of Massachusetts. British and European sanctions on Russian oil purchases remain in place.

The US treasury secretary, Scott Bessent, claimed the waiver – allowing purchases of Russian oil already at sea as of 17 April – would “help stabilise the physical crude market and ensure oil reaches the most energy-vulnerable countries”. Analysts said the waiver may help some individual countries starved of Gulf oil by Trump’s Iran war, but would do little to drive down US gasoline prices, while the Democrats said it would also not stabilise global markets.

Russian drones struck critical infrastructure of Ukraine’s energy firm Naftogaz in the Dnipropetrovsk region over Sunday night, the company said. Among the targets was a filling station, Naftogaz said, adding that the station’s premises and equipment were completely destroyed and two employees injured.

Russia launched 524 drones and 22 missiles at Ukraine over Monday, the Ukrainian air force said. Air defence units shot down or neutralised 503 drones and four missiles. In Russia, drones were downed over Monday night over regions such as Rostov and Belgorod in the south, the Interfax news agency said, citing the defence ministry in Moscow. Two people were killed in Belgorod, local authorities said.

Explosives found on Monday near the debris of a suspected Ukrainian military drone would be disposed of by blowing them up in place, Lithuanian police said. Authorities had previously said the drone was not armed. It was found crashed in the village of Samane and was presumed to have gone off-course en route to a Russian target.