The donation by Sammy Ofer, a tycoon and philanthropist, will be added to £23million from the Heritage Lottery Fund to conserve the 1869 vessel, which is kept at Greenwich, London.

Romanian-born Mr Ofer, who has Israeli nationality, served in the British Royal Navy during the Second World War.

He recently gave £20million to the National Maritime Museum.

The Cutty Sark project, due to be completed by 2010, will have a gallery named after Mr Ofer.