It's a question many European countries are asking: What do they need to do to counter the growing threat from Russia following Moscow's invasion of Ukraine? Last month, the head of the British Army, General Sir Patrick Sanders, mooted the idea of a pre-war, part-time citizen's army to defend the UK. Such an army is already in place in Estonia. Deborah Haynes watched them train on the freezing border with Russia. And their message to Britons is clear: Get off the sofa and learn how to fight. World News updates: https://news.sky.com/story/ukraine-war-latest-uk-sanctions-prison-bosses-at-polar-wolf-colony-where-navalny-died-as-russia-claims-second-frontline-breakthrough-12541713 #estonia #russiaukrainewar #putin #navalny SUBSCRIBE to our YouTube channel for more videos: null Follow us on Twitter: https://twitter.com/skynews Like us on Facebook: https://www.facebook.com/skynews Follow us on Instagram: https://www.instagram.com/skynews Follow us on TikTok: https://www.tiktok.com/@skynews For more content go to http://news.sky.com/ and download our apps: Apple https://itunes.apple.com/gb/app/sky-news/id316391924?mt=8 Android https://play.google.com/store/apps/details?id=com.bskyb.skynews.android&hl=en_GB Sky News Daily podcast is available for free here: https://podfollow.com/skynewsdaily/ Sky News videos are now available in Spanish here/Los video de Sky News están disponibles en español aquí: https://www.youtube.com/channel/UCzG5BnqHO8oNlrPDW9CYJog To enquire about licensing Sky News content, you can find more information here: https://news.sky.com/info/library-sales