The I Kissed a Girl hitmaker was invited to perform at the Democrat politician's inauguration ceremony in January (13) and her parents were keen to watch their daughter sing, despite voting for Obama's Republican rival Mitt Romney in the election.
However, Perry blocked them from the event, insisting it would be wrong for them to attend the inauguration of a president they opposed.
She tells America's Marie Claire magazine, "My parents are Republicans, and I'm not. They didn't vote for Obama, but when I was asked to sing at the inauguration, they were like, 'We can come.' And I was like, 'No, you can't. I love you so much, but that - on principle.' They understood, but I was like, 'How dare you?' in a way."