The print of Prince Charles's work sold for twice the expected amount

The picture of the Highgrove estate which sold for twice its expected value, was among several exhibits auctioned to raise money for a memorial garden for September 11 victims.

The site is being developed in lower Manhattan, near the site where the twin towers fell in 2001.

Sixty-seven Britons died in the attacks, the biggest loss of British life in a terrorist attack.

More than 300 people attended the black-tie gala dinner at Cipriani's on 42nd Street, Manhattan, paying a minimum of �150 ($275) each. Many guests paid much more than the asking price.

During the auction, guests also bid for a private tour of Highgrove, the Prince's Gloucestershire home, by landscape architect Julian Bannerman, which sold for �3,800 ($6,951).

An official Jubilee celebration photograph of the Queen and Duke of Edinburgh, by Lord Lichfield, was sold for �1,600 ($2,926).

Spokeswoman Peggy Brown described the charity auction as "amazingly successful".

Personal and corporate donations amounting to �135,000 ($247,000) have so far been raised for the trust.