David Cameron last night backed plans for the launch of a privately funded new royal yacht to mark the Queen's Diamond Jubilee this year.
The £60m vessel – doubling as a research ship for scientists and a training facility for youngsters – would be a replacement for Britannia which was scrapped in 1997.
But the Prime Minister moved swiftly to scotch any talk of taxpayers' cash being spent on the project at a time when the Government is driving through austerity measures.
Downing Street has backed a scheme championed by the former Royal Navy officer, Rear Admiral David Bawtree, for the nation to give the Queen a yacht as a gift to commemorate her 60th year on the throne. He is understood to have the support of the Prince of Wales and the Princess Royal, and to have already attracted promises of support of £15m for the project.
The Britannia was launched in 1953, shortly after the Queen came to the throne, and carried the Royal Family on voyages totalling more than one million nautical miles before being decommissioned by the Blair government. Supporters said it helped, as a symbol of British prestige, to clinch big foreign business contracts. Its replacement would be a 600ft ship used for trade and business events, as well for scientific research and training courses for disadvantaged youngsters.
It would be leased to the Royal Family for limited periods, including for official visits overseas. However, the Government has made clear it would be impossible in the current financial climate to commit public cash to the project. A report suggesting it could be supported with taxpayers' money had brought instant condemnation from Labour.
The ministers leading support for the project are Michael Gove, the Education Secretary, and David Willetts, the Universities minister. In a letter to Mr Cameron, Mr Gove said: "As a country with a long tradition of monarchy, we should be proud to honour our Queen in this way."
In another letter to Nick Clegg, the Deputy Prime Minister, he argued that events planned to mark the Jubilee, such as street parties and Proms concerts would be transient – and the country should mark the landmark with something more lasting.
Mr Gove also warned of the danger of the anniversary being overshadowed by the London Olympics.
Yesterday, as details of the yacht project emerged, Mr Cameron's official spokesman said the Government would "react favourably" to plans for a privately funded vessel.
"If people come to us and say 'could we do anything to facilitate this and support this', then we would be happy to have those conversations and see what we can do, but it is not a Government proposal," he said.
Earlier Mr Cameron's spokesman had insisted the project could not be supported from the public purse.
Mr Clegg made the same point, saying: "Most people in the country would think the Diamond Jubilee is a wonderful occasion to celebrate together as a community and as a nation. But I suspect most people would think, given there is very little money around, that this probably would not be the top of their list of priorities for the use of scarce public resources."