Jul 1, 2009, 11:00 GMT
Britain's Queen Elizabeth's cousin's flights cost the taxpayer almost £150,000.
Prince Henry, the Duke of Gloucester - who is 19th in line to the throne - and his wife Birgitte flew to Tonga and the Solomon Islands in the South Pacific last August for the Coronation of Tonga's King George Tupou V, leaving taxpayers to foot bill.
The couple's journey from London to New Zealand - with return flights to Britain from Australia - cost £35,413 while charter flights to the islands added a further £114,000 to the price of the trip.
The total cost of the couple's round trip was £149,413.
According to the report, Prince Charles made the most expensive train journey when he travelled to Sheffield, South Yorkshire from London to visit a steelworks, then from Bingley to Warminster on other royal engagements before returning to London's Euston station.
The full cost of the trip was reportedly £26,762.
Yesterday it was reported Britain's Princess Beatrice - who is fifth in line to the throne - lived in an apartment newly-renovated flat in St James' Palace during her first year at London's Goldsmith's College, at a cost of £300,000.
Earlier this week Buckingham Palace accounts revealed each British taxpayer paid 69p towards the royals during the last financial year - up 3 pence on the previous year.
The accounts also show Queen Elizabeth was forced to add to the civil list - which pays for the running of her homes, staff wages and royal events - by withdrawing £6 million from her reserve fund.
The 83-year-old monarch is expected to ask the government to increase the civil list when their current financial agreement ends in December 2010.
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