A Romanian-Israeli shipping magnate has donated £20m to the National Maritime Museum in what is believed to be the largest single donation by an individual to a cultural project in Britain.
Sammy Ofer, 86, a philanthropist and lover of the arts, was hailed as leading the way for a growing breed of billionaires who are choosing to donate substantial proportions of their wealth to artistic causes.
A key figure in the global maritime industry who has forged close links with London's shipping community, Mr Ofer served with the Royal Navy during the Second World War and has expressed his admiration for the nation's seafaring history ever since.
His gift will enable the museum in Greenwich, south-east London, to build a £35m wing in time for the 2012 London Olympics which will include a new space for special exhibitions.
Gordon Brown said: "This generous donation by Mr Ofer will help to ensure current and future generations understand better the crucial role played by the sea in our history and the lives of those who depended upon it."
Mr Ofer, who is now based in Monaco and ranked number 226 in the Forbes world rich list last year, said he was pleased the funds would be used for a good cause.
"I look forward to helping this hugely exciting project and believe it will be a great step forward for the museum," he said.
Born in 1923 in Romania, his family moved to the then-British mandate of Palestine. He entered the maritime world, joining his father's chandlery business, and saw action during the war.
His international business empire includes Zim, one of the largest container shipping companies in the world and he also has a 16.5 per cent (£500m) stake in Royal Caribbean, the world's second largest cruise line. Last year, he set up a £4m fund to establish the Sammy Ofer Heart Institute in Tel Aviv and the Sammy Ofer School of Communications.
Mr Ofer's donation to the National Maritime Museum came after an approach from his friend Lord Sterling, the museum's chairman, who said: "I showed him around the place and he suddenly turned around to me and said 'I'd like to do it'. I was amazed he was serious. Nobody has ever given that sort of support in the past."
The museum's director, Kevin Fewster, said the project, which has been 12 years in the planning, would help put the museum at the forefront for major exhibitions. "It will create a spectacular contemporary environment in which more people can appreciate the wonders of our world class collections and their stories of human endeavour and discovery," he added.
Over recent years, a number of wealthy businessmen and investors have donated generously to British art institutions including John Studzinski, an American investment banker who gave £5m last year towards the Tate Modern's new extension. Anthony D'Offay, the art dealer, also announced last month that he was handing over £125m worth of paintings, drawing, sculptures and photographs at the cost price £26.5m to the Tate Gallery and the National Galleries of Scotland.
Arts & Business, a charity, said its figures showed that private investment in culture had reached a record level in Britain of almost £600m.