Rishi Sunak will meet UK troops in Estonia and Nordic and Baltic leaders at a summit on countering Russian aggression, where he will say leaders must sustain or exceed their lethal aid support to Ukraine and their political backing. Monday’s meeting will come after the UK prime minister was reported to have unnerved some in Whitehall by asking for a “Goldman Sachs dashboard” on the progress of the war and how UK military supplies are used, according to the BBC. Sunak will attempt to reassert his commitment to supporting the Ukrainian war effort. He will announce the UK will supply hundreds of thousands of rounds of artillery ammunition next year to Kyiv in a £250m contract as part of a military aid package, which already includes rocket systems and anti-aircraft guns. The prime minister will travel to Latvia for the leaders’ gathering of Joint Expeditionary Force (JEF) countries, including Denmark, Finland, Estonia, Iceland, Latvia, Lithuania and the Netherlands, which will be addressed by Ukraine’s president, Volodomyr Zelenksiy. “From the Arctic Circle to the Isle of Wight, the UK and our European allies have been in lockstep in our response to the invasion of Ukraine, and we remain steadfast in our ambition for peace in Europe once again,” Sunak said ahead of the visit. “But to achieve peace, we must deter aggression and our deployments across the region together are vital in ensuring we are able to respond to the gravest of threats. I know this Joint Expeditionary Force summit will only underline our close friendships and unwavering support for Ukraine.” No 10 said the meeting would also discuss intelligence sharing between JEF countries, threats to infrastructure and hybrid threats posed by Russian aggression and bolstering support to Finland and Sweden ahead of their accession to Nato. Further announcements on joint military exercises are also expected. Sunak is then expected to fly on to Estonia, where he will meet UK and Nato troops serving on the military alliance’s eastern flank on the Russian border. Ukrainian military figures have renewed their efforts in recent days to implore the west for more weapons to regain the initiative against Russia, after a string of victories in the country’s east but with both sides at a standstill and Russian missile attacks targeting cities and critical infrastructure. A source told the BBC that Sunak had recently requested a data-driven assessment on the progress of the war and the significance of the UK’s military contributions to Ukraine, suggesting there are tensions in Whitehall over the current lethal aid strategy. Adm Sir Tony Radakin, the chief of the defence staff, told the Royal United Services Institute last week that the Ukrainians would be dependent on further weapons supply. “Extraordinary times call for an extraordinary response. This explains why Russia is losing. And the free world is winning … Providing we maintain our cohesion and resolve, the real victory within our grasp is much more significant,” he said. The head of the Ukrainian armed forces, Gen Valeriy Zaluzhny, said more supplies would be necessary to make further gains. “We need tanks, we need APCs [armoured personnel carriers], infantry fighting vehicles. And we need ammunition.”