、。
She's a UK national, but she was born in France.
Literal
She [topic-は] UK [genitive-の] citizen is [but-が], born country [topic-は] France is.
Two contrasting topics with two formal copulas: 国民だが ('is a citizen, but') and 国はフランスである ('the country is France'). The conjunction だが combines the casual copula だ with the clause-final が ('but'), a slightly stiff narrative tone — common in biographical or expository writing. The relative clause 生まれた国 ('the country she was born in') puts past-tense 生まれた directly before the noun with no relative pronoun. である is the formal/literary equivalent of だ, the standard copula in essays, news, and academic prose; here it lends a measured, biographical air. Note how the second clause uses は again to mark contrast — 'her citizenship is X, [but in contrast] her birth country is Y.'