The Princess Royal made a secret stopover as she and her husband, Vice Admiral Sir Timothy Laurence, made their way back to the UK from New Zealand.
As confirmed in the Court Circular, which records all of the royal family's official activities: "The Princess Royal, accompanied by Vice Admiral Sir Tim Laurence, this morning departed Wellington International Airport, New Zealand, for Australia."
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It continued: "Her Royal Highness, Colonel-in-Chief, Royal Australian Corps of Transport, later received Major General Suzanne Graham at Government House, Sydney, upon relinquishing her appointment as Head of Corps and Brigadier Natasha Ludwig upon assuming the appointment.
"The Princess Royal, accompanied by Vice Admiral Sir Tim Laurence, afterwards toured the Royal Botanic Garden Sydney, Mrs Macquaries Road, Sydney."
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Princess Anne placing a wreath in Wellington, New Zealand
The entry for Saturday 18 February also states that the Princess visited New South Wales Mounted Police Stables and Museum.
Anne and Sir Tim landed back at London's Heathrow Airport on Sunday.
The royal was forced to change the schedule of her four-day visit to New Zealand last week as a national state of emergency was declared amid widespread damage across the North Island from Cyclone Gabrielle.
As a result, Anne, 72, did not travel to Palmerston North's Linton Military Camp to mark the Royal New Zealand Corps of Signals' centenary. Her first port of call after landing in Wellington last Tuesday was to the National Crisis Management Centre in the basement bunker of the Beehive.
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Anne also visited Christchurch, New Zealand
The New Zealand Defence Force released a statement on behalf of the Princess, who said she was "impressed by the major efforts being undertaken by first responders, local and national agencies to ensure the best possible support for everyone, especially those still at risk".
She added: "I admire the courage of the people of Aotearoa during this alarming and difficult time.
"You should all be proud of the resilience, strength and care for your communities you are showing in the face of adversity."
Anne and Sir Tim later laid a wreath at a Service of Remembrance at Pukeahu National War Memorial in Wellington.
The four-day trip also saw the former equestrian visit the Riding for the Disabled Association in Porirua, where she was given a demonstration by three different groups of riders and unveiled a plaque to commemorate the occasion.
Friday saw the Princess Royal travel to Christchurch, where she rededicated the Citizens' War Memorial in Cathedral Square.
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