The former Queensland governor has become the country's 25th governor-general taking over from the post vacated this week by Major General Michael Jeffery.

She comes to the head of state role after serving as governor of Queensland for five years.

The chamber, including Prime Minister Rudd, his wife Therese Rein, government ministers, senators and other official guests, applauded after the swearing-in ceremony.

A 21-gun salute was sounded on the forecourt of parliament.

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