The UK Ministry of Defence said on 2 October 2026 that allies in the UK-led Joint Expeditionary Force (JEF) had conducted Exercise Lion Protector 26 across the North Atlantic, High North and Baltic Sea, training to protect critical national infrastructure and test coordination across domains including cyber and space. The announcement came as Defence Secretary Wes Streeting met JEF counterparts at a summit in Keflavik, Iceland.
Infrastructure protection framed as a national security issue
The department said the exercise saw forces train "to protect critical national infrastructure, strengthen joint command and control, and counter emerging threats" across the North Atlantic, High North and Baltic Sea.
It described the region as vital to UK national security, citing "the data cables that connect the UK to the world" and the energy infrastructure that powers homes and businesses. The ministry presented the activity as a response to what it called rising Russian hybrid threats.
The announcement is primarily a defense statement about a multinational military exercise; the infrastructure, cyber and space elements are one part of it.
Cross-domain coordination tested
According to the ministry, Lion Protector launched in August with a rehearsal of a multinational maritime escort operation stretching the length of the Baltic Sea.
Warships and aircraft from Denmark, Latvia, Sweden and the UK escorted a Danish vessel carrying military equipment to Latvia, in what the ministry said tested the JEF's ability to coordinate rapidly across sea, land, air, cyber and space.
The UK's Standing Joint Force Headquarters coordinated activity across the High North and Baltic Sea region and deployed north of the Arctic Circle in Norway to test its ability to command allied forces at speed and range, the ministry said. Royal Marines from the UK's Special Operations Maritime Task Group also carried out maritime interdictions, amphibious landings and vertical ascent training on the Faroe Islands alongside Danish forces, which the ministry said was the first exercise there since the Second World War.
Summit agenda in Keflavik
The ministry said defence ministers meeting in Keflavik would progress discussions on Canada's application for membership of the JEF Framework, and would also discuss deepening cooperation on countering hybrid threats, furthering industrial collaboration, and support to Ukraine through the JEF-Ukraine Enhanced Partnership. Canadian and Ukrainian ministers attended.
It described the JEF as a UK-led coalition of ten nations comprising the UK, Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, the Netherlands, Norway and Sweden, with high readiness forces configured to respond rapidly to crises in support of NATO security.
The ministry said the summit builds on the JEF Leaders' Summit in Helsinki in March, and that Exercise Lion Protector 26 comes ahead of the Atlantic Future Forum and the International Sea Power Conference, both taking place in Oslo in November.
What the Defence Secretary said
Defence Secretary Wes Streeting MP said: "The North Atlantic, High North, and Baltic are the frontline of the UK's security, which is why British leadership of the Joint Expeditionary Force is so vital to our defence."
He added that recent JEF exercises, from amphibious landings on the Faroe Islands to deploying a standing headquarters north of the Arctic Circle, "have shown how Britain is working with our allies to enhance NATO's defence of the region in the face of rising Russian threats." The characterization of Russian activity is the UK government's position.
Key facts and where they come from
- The exercise trained forces to protect critical national infrastructure and counter emerging threats.
train across the North Atlantic, High North, and Baltic Sea to protect critical national infrastructure, strengthen joint command and control, and counter emerging threats
- The UK government cited data cables and energy infrastructure as vital to national security.
From the data cables that connect the UK to the world, to the energy infrastructure that powers homes and businesses
- The August escort rehearsal tested coordination across five domains including cyber and space.
testing the JEF's ability to coordinate rapidly across sea, land, air, cyber and space
- Ministers in Keflavik discussed Canada's application to join the JEF Framework.
ministers will progress discussions on Canada's application for membership of the JEF Framework
- The JEF is a UK-led coalition of ten nations supporting NATO security.
JEF is a UK-led coalition of ten like-minded nations comprising high readiness forces configured to respond rapidly to crises in support of NATO security.
- UK headquarters deployed north of the Arctic Circle in Norway during the exercise.
deploying north of the Arctic Circle in Norway to test its ability to command allied forces at speed and range