Ukrainian President Volodymyr Zelenskyy has voiced significant concerns regarding Russia's renewed efforts to involve its ally, Belarus, in the ongoing conflict. On Friday, Zelenskyy conveyed an intelligence report from Ukraine’s top commander, Oleksandr Syrskyi, indicating a buildup of infrastructure. "According to intelligence, road construction in areas leading to Ukraine and the establishment of artillery positions are going on in the Belarusian border area," Zelenskyy stated on Telegram, expressing his belief that "Russia will once again try to involve Belarus in its war." In response, Ukraine has issued warnings to the Belarusian leadership, emphasizing its unwavering readiness to defend its territory and independence. Zelenskyy further suggested that intelligence points to Russia's attempts to regroup forces, likely to compensate for personnel shortages, which he believes explains the increased military activity observed on Belarusian territory. This development echoes Belarus's prior cooperation, when President Alexander Lukashenko, a close ally of Vladimir Putin, allowed his nation's territory to be used for parts of Russia’s February 2022 invasion.

Amidst these geopolitical tensions, Ukraine has intensified its offensive actions against Russian infrastructure. On Saturday, Ukraine launched drone strikes deep inside Russia, successfully targeting two significant oil refineries. The Novokuybyshevsk refinery in Russia's Samara Oblast was hit in the early hours, sparking a large fire and prompting reports of blasts by local residents. This facility is crucial to Russia's energy sector, processing 8.8 million tonnes of crude annually and producing over 20 types of commercial products essential for supporting Russian forces. Hours later, a second drone strike targeted the Syzran refinery, also in Samara Oblast, causing a fire near a storage tank farm for crude oil and finished petroleum products. The Syzran facility is vital for Russia's domestic fuel supply, river logistics network, and export pipeline system, with the port of Novorossiysk serving as a key shipment hub. Additionally, an industrial facility in Tikhoretsk in Russia's Krasnodar Krai was hit by a separate overnight drone attack, leading to a fire that required over 200 firefighters and dozens of fire appliances to control. These strikes align with Commander Syrskyi's reported strategy earlier in the week, where he stated Ukrainian forces were seeking to reduce Russia’s offensive capabilities by maintaining a high pace of strikes on military, defence-industrial, and other facilities. In March alone, Ukraine struck 76 such targets, including 15 facilities within the oil-refining industry.

Concurrently, Russia launched a massive overnight drone bombardment against Ukraine, deploying 219 drones from the evening of April 17. Ukrainian air defenses demonstrated significant effectiveness, destroying or jamming 190 of these, including Shahed loitering munitions and other types, across the country's north, south, and east. While 28 drones recorded hits at 17 locations and debris from downed UAVs fell at a further nine sites, Ukraine's defense effort involved aircraft, missile units, electronic warfare systems, and mobile fire groups, with some drones still active as of the morning report.

Beyond the immediate conflict, Zelenskyy has proposed that Ukraine's wartime experience in the Black Sea could be instrumental in ensuring freedom of navigation in the Strait of Hormuz. Addressing a video conference attended by 50 countries and chaired by France and Britain, he remarked, "Decisions made regarding Hormuz now will determine how other aggressive actors perceive the possibility of creating problems in other straits and on other fronts." He stressed the need for clear and specific actions to prevent a situation akin to Gaza. Zelenskyy elaborated that over four years of war with Russia, Ukraine has "already carried out a very similar mission in the Black Sea," acquiring extensive experience in escorting merchant vessels, demining, defending against air attacks, and coordinating such operations. Ukraine has also deployed specialists across the Middle East to share its expertise in defending against Russian drones, many of which are Iranian-designed. The nation has solidified security cooperation agreements with Saudi Arabia, Qatar, and the United Arab Emirates, and is engaged in talks with Oman, Kuwait, and Bahrain, indicating its growing role in broader maritime security initiatives.

Meanwhile, the international energy landscape saw notable developments regarding sanctions. Serbia’s Russian-owned NIS oil company secured a 60-day sanctions waiver from the US, allowing it to continue importing crude oil until the sale of its Russian majority stake to Hungary’s MOL is finalized. This followed the expiration of a previous one-month waiver on Friday. The US had imposed sanctions on NIS in October last year as part of broader measures against Russia’s energy sector due to the war in Ukraine, demanding the divestment of Gazprom Neft and Gazprom, its Russian majority owners. Serbian energy minister Dubravka Djedovic Handanovic viewed the latest waiver as a sign of progress in the ownership change negotiations. Separately, the US President Donald Trump's administration on Friday issued a distinct month-long sanctions waiver, allowing the sale of Russian oil and petroleum products that are already at sea. This move, issued by the Treasury Department, extends an earlier effort to soften surging energy prices, despite Treasury Secretary Scott Bessent having previously indicated Washington would not renew the waiver. The license permits the purchase of oil and petroleum products loaded onto any vessel as of this Friday, prolonging an easing of sanctions that expired on April 11, both measures explicitly aimed at easing global supply shocks from the US-Israeli war against Iran.