ITV News Correspondent Dan Rivers hears from the Ukrainian men and women giving up their weekends with families to hone their weapon skills in case they have to defend their homeland
They are willing to be the last line of defence resisting a Russian invasion. The men and women of the 135th Territorial Force are not professional soldiers, but civilians who know how high the stakes might get.
We have travelled 50 km outside of the capital Kyiv to a freezing training ground to watch them being put through their paces with assault rifles provided by the Ukrainian army.
The temperature is hovering just below freezing, but the 135th seem impervious to the cold, practising their combat manoeuvres in the snow.
Hannah Kolesnikova is a keyboard warrior Monday to Friday for an IT firm, but on Saturday is barely recognisable, kitted out in camouflage, learning to handle a weapon in case her life depends on it.
If you believe some of the more dire warnings from the US State Department, soon it might.
Her boyfriend Volodyrmr Halaiko is also here for the war games which have suddenly become much more realistic.
I ask him if he would be willing to die for his country, and he laughs a little nervously, but then tells me while he doesn’t like the idea of "being dead" he would be willing to fight to the death if the Russians come.
Across Ukraine every Saturday, these territorial defence groups are intensifying their training knowing they will become the backbone of a people’s resistance.
Oleksiy Danilov, Secretary of National Security and Defense Council has gone on record to talk about the capacity of this force.
"The entire group who can take weapons at once is 2-2.5 million people. And those who think that 100-120,000 (Russian soldiers) at the border can do something, could they advance (on Ukraine)?
"Yes, they can, but they will face an immediate repulse from here."
That might be a rather optimistic number, but when you consider that the Ukrainian army is about 200,000 strong, together with these civilian defence forces, there would be an ability to mount a significant insurgency against occupying Russian troops.
Hannah and Volodyrmr also point out they would have the advantage of deep local knowledge of the countryside around their home.
The institutional memory of Russia’s ill-fated invasion of Afghanistan looms large in the collective minds of Russia’s Generals.
Rolling the tanks in would be the easy bit - holding a country the size of France and England combined, would be especially costly.