A tourist dived in his underwear from a Sydney ferry and swam ashore to the waterfront mansion of Australia's governor-general, swimming 10 laps of the pool before being arrested on Sunday and sparking a review of security.

The man stunned fellow passengers by stripping to his underwear and diving off the ferry, swimming 600 metres with water police vessels in pursuit, and then climbing the wall of Admiralty House, across from the Opera House, police said.

The Sydney residence of Prime Minister Kevin Rudd is adjacent to the governor-general's mansion.

"He evaded water police by entering the grounds of the residence. He then dove into the pool until he was directed out by police," a police spokeswoman told Reuters.

The two-storey house, built in 1845, is the Sydney residence of the Queen's representative in Australia, the governor-general, and has spectacular gardens, colonnaded verandahs and views of the adjacent Harbour Bridge and surrounds.

The grounds of Admiralty House were used to host U.S. President George W. Bush and other world leaders during an Asia-Pacific summit last year and the house is often used by Queen Elizabeth when in Australia.

Neither the Governor-General Michael Jeffery, nor Prime Minister Rudd were home at the time.

Police said the 45-year-old man, from Queensland state, roamed the gardens before diving into the pool, where he was found some minutes later by red-faced security guards.

Security at the walled residence was now being reviewed to see how the man got ashore so easily, authorities said.

The man, who waved to onlookers in television images and who police said acted as if the incident was a joke, was charged with trespass and entering a government property. He was bailed to appear in court later this month.