The leaders of the UK, Ukraine, France and Germany have discussed the “urgent need” to ramp up production of defensive weapons and deep-strike capabilities after Russia fired Oreshnik missiles at Ukraine, Downing Street said.British prime minister Sir Keir Starmer hosted Ukrainian leader Volodymyr Zelenskiy along with French president Emmanuel Macron and German chancellor Friedrich Merz – some of Kyiv’s staunchest allies – at No 10 on Sunday evening for talks on the war.The leaders called on Russian president Vladimir Putin to agree “an immediate and complete ceasefire”, with the current line of contact as a starting point for any negotiations, Downing Street said.A readout said the leaders “condemned Russia’s large-scale missile and drone attacks – including the repeated use of the Oreshnik missiles – on Ukrainian cities with a tragic toll on civilians, as well as irresponsible and dangerous Russian drone incursions into Nato territory.“They expressed their condolences to all the victims.“They discussed how to use the upcoming G7 summit at Evian, the next meeting of the ‘coalition of the willing’, and the Nato summit at Ankara to best co-ordinate further support for Ukraine based on its prioritised needs, including further pressure on Russia’s war economy and an increased pledge of military and defence support for Ukraine at the Nato summit.“The leaders underlined the urgent need to scale up the production of interceptors and co-develop anti-ballistic missile and deep strike capabilities, and to support the future sustainability of the Ukrainian armed forces.”Ukraine earlier said Moscow’s forces had struck a nuclear fuel storage facility near the mothballed Chernobyl power plant north of Kyiv, an incident that drew a sharp retort from the UN’s atomic watchdog.The Ukrainian military said a Russian Shahed drone hit a building that is part of the central spent fuel storage facility within the Chernobyl exclusion zone. A small fire was extinguished within an hour, the Ukrainian General Staff posted on Telegram. Ukraine had meanwhile launched a drone barrage at St Petersburg on Saturday, the final day of Russia’s premier investment forum, hours after Putin had rejected a proposal for talks with Kyiv and ahead of Zelenskiy’s meeting with European leaders.The International Atomic Energy Agency (IAEA) said it had been informed of the Chernobyl attack and its team would soon visit the facility and inspect the damage.The facility is used to provide long-term storage for spent nuclear fuel from Ukraine’s operating atomic power plants.“The strike caused significant damage to the facility’s fuel reception building – including to the facade, windows and doors – and nearby buildings were also affected by the blast wave,” the UN’s nuclear watchdog said. Radiation levels at the facility remain within established limits, according to Ukraine.Ukraine’s foreign ministry and energy ministry “are already working to ensure that each of our partners knows what has happened,” Zelenskiy said on X, describing the strike as “extremely vile”.“As of now, there are no readings exceeding normal background radiation levels. But there is certainly an increase in Russia’s brazenness,” Zelenskiy said.Rafael Mariano Grossi, director general of the IAEA, said the incident was “deeply concerning, as it occurred at a facility containing large amounts of nuclear material, held in storage just metres away from the attacked building”.[ The €500m hole in Chernobyl’s roof: A race to repair damage from a Russian droneOpens in new window ]The Chernobyl incident comes a week after Moscow claimed a Ukrainian drone had hit the idled Zaporizhzhia nuclear power plant in southeast Ukraine, which Russian forces have controlled since the first weeks of the war.The IAEA also inspected the Zaporizhzhia site following the strike and confirmed it was a drone attack. Ukraine’s southern military command denied any strikes against the facility.Putin had on Friday rejected Zelenskiy’s call to meet and negotiate an end to the war, now well into its fifth year, which the Ukrainian president made in a lengthy open letter on Thursday that suggested Switzerland, Turkey and Arab countries as potential venues.“I see no sense” in holding a meeting with Zelenskiy, Putin said at the St Petersburg International Economic Forum. The Russian leader said he had skimmed through Zelenskiy’s letter and said the tone was “rude”.Saturday’s drone strikes at St Petersburg, about 1,000km north of Kyiv, and the surrounding region set a defence ministry facility ablaze and disrupted operations at Russia’s second-largest commercial airport for several hours.[ Russia is showing signs of weakness in Ukraine. So it hits harderOpens in new window ]The two sides continued an exchange of drone fire into Sunday. Russia’s defence ministry said it intercepted 95 Ukrainian drones overnight across more than a dozen regions. Ukraine reported attacks from 236 Russian drones, of which it said 215 were shot down in the north, south and east of the country.Separately on Sunday, Ukrainian forces struck the Chongar Bridge, temporarily blocking an access point to the Crimean peninsula, Valdimir Saldo, governor of the occupied Kherson region in southeast Ukraine, said on Telegram. – Bloomberg/PA