Ukraine has called for the west to supply Patriot missiles batteries and other modern air defence systems, amid growing concern that attacks by Russia on its electricity grid could prompt a new wave of refugees from the wartorn country. The country’s prime minister, Denys Shmyhal, speaking on Monday before a Ukraine humanitarian aid conference the following day in Paris, said Russia wanted “to trigger another wave of migration toward Europe” during the depths of winter. So far the US has resisted supplying Ukraine with the sophisticated air defence systems, while a recent attempt by Poland to get Germany to deploy a Patriot battery into the country was rejected by Berlin. Ukraine’s president, Volodymyr Zelenskiy, also pressed US leader Joe Biden for more help in protecting the country’s battered energy grid in a Sunday night phone call, although he did not publicly specify what weapons he wanted. Waves of Russian attacks since October had destroyed 50% of the network, he added. “The President also emphasised the importance of capable air defence. Volodymyr Zelenskiy called on President Biden to do everything possible to help protect the civilian population of Ukraine and its critical infrastructure,” Kyiv said in its readout of the conversation between the two. The White House emphasised in its readout that the US had authorised a further $275m of military aid on Friday, including rockets for the Himars artillery system. But the Pentagon has shown no sign of approving the export of Patriots, best known for knocking out Iraqi Scud missiles in the first Gulf war. On Monday afternoon, Zelenskiy addressed a virtual meeting of G7 leaders, where he warned that Russia “still has the advantage in artillery and missiles” and he called for modern tanks, long-range missiles – and an extra “two billion cubic meters of gas” to make up for shortfalls in electricity supply. But while G7 leaders agreed in a post-meeting statement that there should be “an immediate focus on providing Ukraine with air defence systems and capabilities”, Germany, the holder of the G7 presidency, said specific weapons deliveries to Ukraine were not on the agenda. Overnight, all non-critical infrastructure in the port city of Odesa was without power. Two people were killed in Russian shelling of the recently liberated city of Kherson, and another two died after a rocket attack on the town of Hirnyk in the Donetsk region, in the east of the country. In London, former prime minister Boris Johnson took another tack, calling on the defence secretary, Ben Wallace, in the Commons to arm Ukraine with long range ATACMS missiles to “take out” the launch sites of Russian drones and missiles that are currently battering the country’s civilians and its power grid. Long sought by the Ukrainians, the missiles have a range of up to 300km, but so far the US and its allies, including the UK, have declined to supply them because they could be used to hit targets inside Russia. Supplying them would help “bring the war to an end as soon as possible”, Johnson said. Wallace did not rule anything out, saying that continued targeting of the electricity grid by Russia may prompt a change of policy: “Should the Russians continue to target civilian areas and try and break those Geneva conventions, then I will be open-minded to seeing what we do next.” An under pressure electricity network and plunging temperatures are already prompting increased refugee flows out of Ukraine. Poland’s president, Andrzej Duda, said the number of refugees in the country “has risen to some 3 million” after talks with his German counterpart in Berlin. The head of Norway’s refugee council also predicted that “hundreds of thousands more” will be forced to leave Ukraine. Jan Egeland said he feared “the crisis in Europe will deepen” as the “the horrific and unlawful bombing of civilian infrastructure makes life unliveable in too many places.” EU foreign ministers meeting in Brussels agreed an extra €2bn (£1.7bn) for a fund that has been used to supply Ukraine with weapons, to replenish the European peace facility that was established last year with €5bn. The €2bn topup was approved despite concerns about Hungary’s “blackmail diplomacy”, after Budapest blocked an €18bn financial aid package for Ukraine last week. Hungary has previously signed off on the EU weapons fund for Ukraine, although it does not allow arms to pass through its territory. The EU is discussing its ninth round of sanctions against Russia, which include bans on the sale of drones and parts. Officials are concerned that Iranian weapons used in Ukraine, including drones, are being part manufactured in Europe – and it agreed to sanction four Iranian military leaders and four organisations it said were supplying drones to Russia.