The Luminaries author and Man Booker Prize winner attracted controversy last week after comments she made at the Jaipur Literary Festival in India were published on the Live Mint news website.
She said she was angry with the Government, which cared only about short-term gains.
"I feel uncomfortable being an ambassador for my country when my country is not doing as much as it could, especially for the intellectual world," she said.
Appearing on TVNZ's Breakfast show this morning, Mr Key said Catton's views on politics shouldn't be taken any differently than those of any other New Zealander.
"She has no particular great insights into politics, she is a fictional writer. I have great respect for her as a fictional writer [sic]."
Mr Key conceded he had read some, but not all of the Luminaries.
"Obviously it's done phenomenally well and I'm really proud of her, but it would be no different from Richie McCaw or the Mad Butcher or anybody else having a view on politics.
"They're absolutely entitled to do that, but her views on politics are no more authoritative than anybody elses.
"I mean, if it's Corin Dann, and he's the chief political reporter, then his comments carry more weight because that's what he does for a job."
Catton posted a statement on her blog in response to the controversy that followed her comments.
"The New Zealand mainstream media, though quick to flare up over a condensed record of remarks made last week in Jaipur, are in general altogether behind the ball: I've been speaking freely to foreign journalists ever since I was first published overseas, and have criticised the Key government, neo-liberal values, and our culture of anti-intellectualism many times," she wrote.
"One reason why my remarks have not have been noticed in New Zealand until now may be that in most modern democracies a writer expressing an opinion is not considered, in itself, shocking.
"The truly shocking thing would be the writer who only spoke in praise of her country; who was unequivocal in gratitude and platitude; who swore fealty to her government, rather than to deep-felt values or ideals; who regarded arts funding as hush money and a part-time teaching position as an intellectual gag.
"I hope that that author does not exist today; but if she does, she is the one who should make the news."
In a subsequent interview with the Guardian, Catton criticised "the scale and shabbiness of this jingoistic national tantrum", which she said "shames me deeply as a New Zealander".
"I believe it can be countered only with eloquence, imagination, and reasoned debate - qualities that might seem to have disappeared from our national conversation, but that persist, and will continue to persist, despite efforts to humiliate and silence those who speak out."
By Brendan Manning of NZME. News Service
