European Union leaders met in Brussels on Monday seeking to overcome Hungarian opposition to an embargo on Russian oil, as Moscow’s forces made gains in the eastern Donbas region of Ukraine. Ukrainian President Volodymyr Zelensky was set to address leaders at the emergency summit, expected to press the block “to kill Russian exports” as he seeks to crank up international pressure on Moscow. In Washington, US President Joe Biden said he would not send rocket systems to Ukraine that could hit Russian territory, despite urgent requests from Kyiv for such weapons and extensive US military aid for Ukraine since the war began. EU diplomats have drafted a watered-down agreement that would see pipeline oil exempted from the ban, in the hopes of unblocking talks on the bloc’s sixth round of Russian sanctions. Ahead of the meeting, Hungarian Prime Minister Viktor Orban told reporters the proposal was a “good solution” but warned there was “no agreement at all” as things stood. On the ground, Russian forces pressed their offensive in Donbas. The situation in Severodonetsk, just across the Donets river from its sister city of Lysychansk, was “very difficult”, the local Lugansk regional governor Sergiy Gaiday said in a statement on social media. “The Russians are advancing into the middle of Severodonetsk”, while the fighting continued, Gaiday said. “We are not going to send to Ukraine rocket systems that can strike into Russia,” Biden told reporters in Washington. Ukraine has received extensive US military aid since with legislators approving another $40 billion (37.1 billion euros) assistance package earlier in May. France’s new foreign minister Catherine Colonna said on a visit to Kyiv that Paris was ready to boost military aid to Ukraine to help it counter Russia’s invasion. France will “continue to reinforce arms deliveries,” Colonna said at a news conference with her Ukrainian counterpart Dmytro Kuleba. The arms would arrive “in the coming weeks”, she said. The highest-ranking French official to visit the capital since Russia invaded Ukraine on February 24, Colonna also visited the town of Bucha, where Russian troops have been accused of committing war crimes against the civilian population. “This should never have happened. It must never happen again,” Colonna told reporters after visiting an Orthodox church in the town. The foreign minister’s visit came as a French journalist was killed while working in Ukraine. Frederic Leclerc-Imhoff was “on board a humanitarian bus” when “he was mortally wounded,” French president Emmanuel Macron wrote on Twitter on Monday. Speaking alongside Colonna, Kuleba said he hoped “divisions will be overcome” at the EU leaders meeting. A sixth wave of EU measures against Moscow was put on the table weeks ago, but has been rejected by Orban and resisted by neighbouring countries also reliant on pipelined Russia oil.