By Deborah Haynes, security and defence editor
The war in Ukraine has had its European allies on alert ever since Russia began its full-scale invasion.
Just yesterday, NATO chief Mark Rutte warned its member states are "Russia's next target".
The bloc, he added, must make all efforts to prevent a war that could be "on the scale of war our grandparents and great-grandparents endured".
In the UK, we've heard from the armed forces minister, who says the country is "rapidly developing" plans to prepare for the possible outbreak of war.
Underlining the role civilians would have to play in a major conflict, Al Carns said armies, navies and air forces respond to crises but "societies, industries and economies win wars".
He said: "The shadow of war is knocking on Europe's door once more. That's the reality. We've got to be prepared to deter it."