Elisabeth Braw, the author of The Undersea War, tells Sky News Defence Insider that Polish reports of Russia briefly breaching its airspace is “troubling” Listen now via Sky's Defence Insider ➡️ https://trib.al/Y9oXDkB 3 month free trial for new customers. Cancel before trial ends to avoid charges. After free trial, subscription auto-renews at standard charges (currently £14.99 per month / £134.99 per year). Cancel anytime effective from next billing date. #russia #ukraine SUBSCRIBE to our YouTube channel for more videos: http://www.youtube.com/skynews Follow us on X: 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 Why not listen to one of our podcasts? This is Why, available for free here: https://podfollow.com/thisiswhy or Ed Conway's Stuff Matters, available here: https://podfollow.com/stuff-matters To enquire about licensing Sky News content, you can find more information here: https://news.sky.com/info/library-sales