Rishi Sunak made a £2.5bn commitment to Ukraine’s defence on Friday during a visit to Kyiv, and pledged that the UK would not falter at a time when military aid from the US has stalled. Sunak met the country’s president, Volodymyr Zelenskiy, embracing him warmly, and addressed Ukraine’s parliament, the Verkhovna Rada. The two leaders held talks and signed a new UK-Ukrainian security treaty. It guarantees that the UK will give “swift and sustained” help should Russia attack Ukraine again. Zelenskiy described the pact, which will remain in force until Ukraine joins Nato, as unprecedented. “Today is the day when the history of Europe changed,” he said, describing the UK, one of Ukraine’s staunchest allies, as a prominent global power involved in a joint task to stop Russian aggression. Sunak said Ukraine had fought with great courage over two years to repel “a brutal Russian invasion”. “I am here today with one message: the UK will also not falter. We will stand with Ukraine, in their darkest hours and in the better times to come,” he said, shortly before he arrived by train in an icy Kyiv. Speaking at a joint press conference in the Mariinskyi palace, Zelenskiy’s neo-classical official residence, Sunak said the UK was the first ally to sign a multi-year security deal with Ukraine. “It sends a strong signal to Putin and others that we are here to stay,” he said, and demonstrated that Britain had patience and resources. “We are here to support Ukraine in the long term,” he emphasised. The UK’s latest military pledge is worth £2.5bn to Ukraine in 2024-2025, an increase of £200m on the previous two years. The package features thousands of shells, long-range missiles and training for the Ukrainian military. At least £200m will be spent on hi-tech combat drones, most of which will be made in Britain. It represents the largest delivery of unmanned aerial vehicles (UAVs) by any country, Downing Street said. They will include long-range strike drones, capable of hitting Russian targets well beyond the frontline, and maritime drones, which Ukraine has deployed successfully against Moscow’s Black Sea fleet. Sunak’s surprise visit is a much-needed boost for Zelenskiy’s government and the first this year by a G8 leader. It came hours after the US and UK launched airstrikes in Houthi-controlled areas of Yemen intended to halt attacks on ships in the Red Sea. The new financial pledge, however, represents only an incremental increase in UK bilateral assistance. It is a fraction of the $60bn in US funding which Republicans in Congress are currently blocking. Zelenskiy said 0n Friday that he was optimistic aid from Washington would arrive. The EU, meanwhile, has so far delivered only 300,000 of 1m artillery shells promised last year. Ukrainian commanders say the Russian army has a greater number of munitions and soldiers, as well as armoured vehicles and aviation. It is now seeking to advance in the east of the country and has launched attacks across a 600-mile-long frontline, but is yet to make a significant military breakthrough. Sceptics pointed out that Ukraine has received western security commitments before, which the Kremlin subsequently violated. The US, UK and Russia signed the Budapest memorandum in 1994, giving Kyiv security guarantees. In return Ukraine gave up its Soviet-era nuclear arsenal. Ukraine’s former defence minister Andriy Zagorodnyuk described the British move on Friday as a “big deal”. “It’s a huge announcement, particularly given the freeze we currently see from the US,” he said. The UK had “stepped ahead” when some allies were hesitating, he added. It was part of a pattern of leadership in which London had provided tanks to Kyiv and encouraged the supply of F-16 fighter jets, Zagorodnyuk said. “It’s hugely appreciated,” he added. “It’s extremely important because this war is more and more about UAVs. They play a critical role.” British drone manufacturers would be able to test “innovative and competitive” designs in real conditions on the battlefield, he suggested. Sunak made his first visit to Ukraine in November 2022, weeks after entering No 10. On Friday the prime minister met Ukrainian emergency workers in Kyiv and toured buildings damaged in recent Russian missile strikes. He announced a further £18m in aid to defend Ukraine’s energy infrastructure and help civilians caught up in the fighting. Yuriy Sak, an adviser to Ukraine’s strategic industries ministry, said the British package “could not have come at a more appropriate moment”. He said it “sent the right signal” to Kyiv’s partners and added: “It’s clear that victory is now won not only on the battlefield but is also forged in design bureaux, factories and training grounds”. Russia’s former president Dmitry Medvedev was unimpressed with the UK-Ukrainian security deal and said Moscow could hit “British representatives” with cluster munitions. “I hope that our arch enemies, the impudent British, understand that officially stationing their troops in Ukraine would mean declaration of war against our country,” he posted on X.