Sir Keir Starmer told European leaders they must realise it is “time to act” because they stand at a “crossroads in history”, following a defence summit on the war between Ukraine and Russia. The Prime Minister unveiled a four-step plan drawn up by leaders at yesterday’s meeting, including a pledge to “develop a coalition of the willing” to defend a deal in Ukraine and guarantee a peace settlement. Sir Keir announced a £1.6 billion finance deal that will allow Kyiv to buy more than 5,000 missiles, after the gathering at Lancaster House in London. He said “every nation must contribute” in the best way it can and a number of “important steps” were agreed. “First, we will keep the military aid flowing and keep increasing the economic pressure on Russia to strengthen Ukraine now,” Sir Keir said. “Second, we agreed that any lasting peace must ensure Ukraine’s sovereignty and security, and Ukraine must be at the table. “Third, in the event of a peace deal, we will keep boosting Ukraine’s own defensive capabilities to deter any future invasion. “Fourth, we will go further to develop a coalition of the willing to defend a deal in Ukraine and to guarantee the peace. “Not every nation will feel able to contribute but that can’t mean that we sit back. Instead, those willing will intensify planning now with real urgency. The UK is prepared to back this with boots on the ground and planes in the air, together with others. Europe must do the heavy lifting.” Among the attendees at the summit were Ukrainian President Volodymyr Zelensky – who afterwards flew to Sandringham to meet the King – and French President Emmanuel Macron, who both met US President Donald Trump at the White House this week. Canadian Prime Minister Justin Trudeau, European Commission President Ursula von der Leyen and Spanish Prime Minister Pedro Sanchez were also seated around the table of 19 leaders at the gathering in central London. Sir Keir said that leaders had agreed to “meet again very soon” to keep up work on the plans. “We are at a crossroads in history today,” he said. “This is not a moment for more talk. It’s time to act. Time to step up and lead, and to unite, around a new plan for a just and enduring peace.” Yesterday’s summit came as leaders continued to rally round Mr Zelensky following his confrontation with Mr Trump in the Oval Office on Friday. The Prime Minister said that he does not accept the US is an “unreliable ally” in the wake of the meeting in Washington DC. He told a press conference that “the US has been a reliable ally to the UK for many, many decades, and continues to be”. He added: “There are no two countries as closely aligned as our two countries and our defence, our security and intelligence is intertwined in a way no two other countries are, so it’s an important and reliable ally for us.” As the summit was taking place, more than a thousand pro-Ukrainian protesters gathered less than a mile away outside Downing Street. Urgent calls were made for European leaders to come together and find a path to peace, and speakers repeatedly thanked the UK for its support after Sir Keir Starmer's warm welcome to the Ukrainian president on Saturday. Mr Zelensky flew straight from yesterday’s summit in a military helicopter to the King’s Sandringham estate in Norfolk, landing at around 5.25pm. Local people, some holding Ukraine flags, gathered outside the estate to try to witness the president’s arrival in Norfolk for his meeting with the King. The meeting took place in the Saloon at Sandringham House, and a helicopter could be seen departing the estate at 6.35pm. While Mr Trump’s US administration is responsible for brokering peace talks with Russia, Sir Keir believes European powers must play a part in enforcing any deal. He has sought a security guarantee from America, aimed at deterring Russian president Vladimir Putin from breaking a future peace agreement. Mr Trump suggested he was not minded to support such a proposal, claiming the British “can take care of themselves” when asked about backing up peacekeeping efforts. Sir Keir said a US backstop is subject to “intense” negotiations. Earlier, First Minister John Swinney said the UK “shouldn’t be talking” of giving Mr Trump another state visit in light of the “unacceptable” scenes in the Oval Office. He has called on the offer of a state visit to the UK to be rescinded unless the US president gives “full scale” backing to Ukraine. Speaking at Bute House, his official residence in Edinburgh, the First Minister said Mr Zelensky was “the courageous leader of the courageous Ukrainian people” and a “completely unacceptable sequence of events” had taken place at the White House. He said: “Until such time as we know the United States are going to be full scale partners with us and allied with us in protecting Ukrainian independence – which is fundamental to the protection of European liberal democracy – then I don’t think we should be talking about a second state visit for President Trump.” The First Minister said he would still engage with the president if he decided to come to Scotland, where he owns two golf courses and has family roots. The SNP leader said he is supportive of the concept of a European assurance mechanism in Ukraine, but said MPs must vote on any plan put forward by the UK Government. In response to calls to expand the UK’s armed forces, Mr Swinney said there needs to be an “open debate” on defence priorities. He said: “I don’t think I’ve felt at any moment in my life that there is such a degree of uncertainty about the international situation as I feel at this particular moment. “So that will raise important questions about defence, but we’ve got to have an open and comprehensive conversation about that.” Pressed on how any increase in defence spending should be paid for, given the SNP’s opposition to cutting international aid, he said: “I think we’ve got to have that honest debate about taxation priorities. “I think the UK had a completely false debate about tax at the general election last year.” The Prime Minister said he would not be driven into a debate on the state visit for Mr Trump. “I’m not going to be diverted by the SNP or others trying to ramp up the rhetoric without really appreciating what is the single most important thing at stake in Europe,” the Prime Minister told the Sunday with Laura Kuenssberg programme. On Thursday, Sir Keir presented Mr Trump with a letter from the King which suggested meeting at Balmoral in Aberdeenshire or Dumfries House in East Ayrshire ahead of a state visit.