Volodymyr Zelenskiy has failed in a last-ditch effort to secure an invitation for Ukraine to join Nato after leaders of the 31 countries signed off on a declaration that did not give a firm timetable or clear conditions for its eventual membership. The frustrated Ukrainian president had accused Joe Biden and other leaders present at a summit in the Lithuanian capital, Vilnius, of showing disrespect and complained that there was “no readiness” to invite his country to join. But the dramatic lunchtime intervention on Tuesday had no impact on the final summit communique, issued a few hours later. It said that while “Ukraine’s future is in Nato”, the alliance would only “extend an invitation to Ukraine” when Kyiv had completed certain “democratic and security sector reforms”. Zelenskiy said, in a statement issued after the communique: “Today I embarked on a trip here with faith in decisions, with faith in partners, with faith in a strong Nato. In a Nato that does not hesitate, does not waste time and does not look back at any aggressor … And I would like this faith to become confidence.” The communique’s language reflects opposition from Germany and the US that too firm a commitment could prompt an escalation from Russia and, if Ukraine was allowed to join the alliance while the conflict continued, it could ultimately bring Nato into a war against Moscow. Zelenskiy had in his earlier statement said Ukraine “deserves respect” and the president, who is not due to meet Nato members formally until Wednesday, complained that “certain wording is being discussed without Ukraine”. “It seems there is no readiness neither to invite Ukraine to Nato nor to make it a member of the alliance,” Zelenskiy wrote, saying this would give Russia the opportunity “to continue its terror” by leaving open the possibility for it to bargain over Ukraine’s future Nato membership in any peace deal. It was a rare departure from Zelenskiy’s international appearances, in which the war time leader has sought to woo western nations with carefully calibrated statements aimed at winning broad support to help him fight off the Russian invaders. Nato sources said they believed Zelenskiy had been engaging in last-minute hardball public diplomacy in the hope of prompting a rewrite of the final summit declaration before the two-day gathering closed on Wednesday. On Sunday, before the summit, Biden said Ukraine was not ready for membership and needed to show progress on “democratisation” and “a whole range of other issues”. But there were signs on Tuesday that not all alliance members agreed with the approach. Petr Pavel, the president of the Czech Republic, said in an interview with Sky News that any agreement that did not allow Ukraine to start the process of joining Nato once the war ended would “probably not be satisfactory”. Ben Wallace, the UK defence secretary, went further in an interview, arguing that Ukraine had already demonstrated it was “a healthier democracy” as it fought against Russia and that “whenever the conflict finishes, we should be prepared as quickly as possible to bring Ukraine closer”. Ukraine believes Nato membership is the only viable solution to prevent future attacks on it by Russia, but the US and other alliance members fear allowing Ukraine to join at some future point could be interpreted by Moscow as escalatory. Western leaders, however, remain keen to emphasise other forms of ongoing support to Ukraine. On Wednesday the G7 leading economies, including the UK, will commit to a framework of long-term security arrangements aimed at guaranteeing long-term weapons supply and economic support to Ukraine while the war continues. “We are stepping up our formal arrangements to protect Ukraine for the long term,” Sunak said, arguing that the mutual declaration to be published by the G7 on Wednesday is intended to make a joint commitment that Ukraine “is never left vulnerable to the kind of brutality Russia has inflicted on it again”. The UK also said it would give a further 70 combat and logistics vehicles to Ukraine, plus thousands of rounds of ammunition for the 14 Challenger 2 tanks already donated. A further £50m contract would help the UK continue to provide spare parts, technical support and maintenance training on equipment already supplied. Several Nato members have announced they have supplied or would supply Kyiv with more weapons, or would enhance military spending. France said it had sent Scalp long-range missiles to Ukraine, the equivalent of Storm Shadow weapons previously sent by the UK. Germany said it would lift its defence budget to 2% of GDP – a longstanding Nato target – next year. Ukraine also said it had reached agreement with 11 countries to help train its pilots to fly Nato standard F-16 fighter aircraft. The step is considered a precursor to Kyiv eventually acquiring the warplanes but it is unclear if the US will give permission for them to be donated before or after the end of the war. “It’s official: a coalition for F-16 training of the Ukrainian air force has been formed,” said Oleksii Reznikov, the Ukrainian defence minister. Sunak said such actions would “send a strong deterrent message to the Russians” and Vladimir Putin had to understand “there is no point in just waiting out the west”. Russia said it was monitoring the summit closely. “Russia is perceived by them [Nato leaders] as an enemy, as an adversary. It is in this vein that the discussions will be conducted,” the Kremlin spokesperson, Dmitry Peskov, said earlier on Tuesday. Leaders meet for a dinner on Tuesday evening, and most will hold post-summit press conferences around Wednesday lunchtime. Biden is due to give a speech in the afternoon when he will set out his position, and is not expected to take questions.