• matter of national significance – вопрос государственного значения
• project of national significance – проект государственного значения
См. также: of similar import, of the same name, of sound mind and disposing memory, of foreign origin
A matter of national significance rests on whether they can secure a swift return to the Premier League 12 months after they were relegated. (BBC)
Why was an idiotic bit of private banter being treated as a matter of national significance? (Daily Mail)
We were told that this was a matter of national significance. (Parliament of Australia)
Gardening guru Costa Georgiadis has described a new food forest initiative in Lyneham as a "project of national significance". (The Canberra Times)
