YA historical fiction set in soviet Eastern Europe with a romance element, maybe published 1970s-80s, possibly about the Prague Spring?

I would have read this book from the library at some point in the 90s in England... I feel like the author was male and had written many other historical fictions and I'm fairly sure it was published before the 90s. All I can remember about this one is Czech/Prague setting and maybe it was about the Prague Spring? I remember the cover was the guy leading the girl away from a fire or something like that...