Volodymyr Zelensky has warned that 'small mistakes can break big friendships' after Reform UK councils began taking Ukrainian flags down from town halls.Councils raised Ukrainian flags following Russia's invasion in 2022, but some Reform-run local authorities have now lowered these in favour of flying local flags and the Union Jack. However President Zelensky has said he hopes they change their course in an interview with The Guardian after he met with Sir Keir Starmer, Emmanuel Macron and Friedrich Merz at Downing Street on Sunday.He said: 'I hope they will put it back. I don't want to be involved in any political things, but you know, the world is so sensitive today. 'Sometimes little, small mistakes can break big friendship or huge contacts.'Mr Zelensky then suggested that 'people have to not make mistakes', adding: 'Okay, so you did it, please let's come back to the table, let's speak, let's understand each other.'It comes after Reform last month came under fire for banning the Ukrainian flag from town halls. The party said it would only fly local flags, the Union Flag and the St George Cross from council buildings in its control. Ukrainian president Volodymyr Zelensky at the 8th European Political Community summit in Yerevan, Armenia, on May 4 Reform UK chairman Zia Yusuf is pictured at last year's party conference in BirminghamReform stormed to victory in ten local authorities in England, including Durham, Lancashire and Staffordshire, in May's local elections. Party chairman, Zia Yusuf, subsequently said Reform's councils 'will move at speed to resolve that the only flags to be flown on or in its buildings will be the Union Jack and St George's flag'.He added: 'No other flags will be permitted to be flown on its flagpoles, balconies, reception desks or council chamber walls.' The party later clarified that county flags would also be permitted. Elsewhere in his interview with The Guardian on Monday, Mr Zelensky also stressed how much his country and Britain need one another in Europe's standoff against Russia.He said: 'British people helped us from the very beginning of this war, it's true. It's because of security, not only values… But it's about security in Europe. It's in the interests of the UK.'Mr Zelensky also revealed that he plans to invite the King for a state visit as early as this year after Charles's show of support for him following the Ukrainian leader's blistering row with Donald Trump in the Oval Office last year.The King and Mr Zelensky met for a private audience on Monday. Left to right: German Chancellor Friedrich Merz, Ukrainian president Volodymyr Zelensky, Prime Minister Sir Keir Starmer, and French president Emmanuel Macron. Here, they are pictured outside Downing Street on June 7In an interview with Sky News, Mr Zelensky earlier revealed that Roman Abramovich has acted as a go-between for Kyiv and Moscow on plans for peace talks.He told the broadcaster that the former owner of Chelsea football club had met him in Kyiv with a message from Russia and offered to bring a reply directly to Vladimir Putin.The Ukrainian leader said Mr Abramovich 'wanted to give me the message that they (Russia) are ready to, that they want to understand what we are ready to do', and had offered to take a reply 'and give it to Putin'.He added: 'I said the question is not about us. You are fighting against us on our territory.'And I said to him about Donbas, it was the key message, I said we will not leave and we will not go out from our territory.'No, we will not give you a victory in such a way, and you will not get it.'Mr Zelensky said he told Mr Abramovich to tell the Russian president he was willing to meet 'any time from tomorrow' in any location other than Russia or Belarus, and either bilaterally or with Mr Trump and European leaders.He did not say when the meeting took place, but the Financial Times reported the pair had met in late May this year.Mr Abramovich was sanctioned by the UK shortly after Russia's full-scale invasion of Ukraine in 2022 over his connections to Mr Putin.He has previously been involved in negotiations with Moscow and reportedly played a role in arranging a prisoner swap in 2022 that secured the release of five British men captured while fighting for Ukraine.In a joint statement on Sunday night, Sir Keir, Mr Macron and Mr Merz called on Putin to agree 'an immediate and complete ceasefire' and condemned Russia's 'large-scale missile and drone attacks' on Ukrainian cities.On the same day, a Russian drone strike killed three people waiting at a bus stop in south-eastern Ukraine, while a separate attack damaged a storage centre for spent nuclear fuel nine miles from the Chernobyl power plant. Officials said radiation remains within safe levels.