Complex sentence: Nesbø is likely to be familiar with the play, which is a classic of Norwegian culture (and of world theatre in general); the writer did not, however, made any statement on the possible connection between Ibsen's character and his own.
Split into simpler sentences: Nesbø is likely to be familiar with the play, which is a classic of Norwegian culture (and of world theatre in general). The writer has not, however, made any statement on the possible connection between Ibsen's character and his own.