The Ministry of Defence has already put back the £3.9bn supercarriers, to be based in Portsmouth, by between one and two years.

But there has been speculation of further cuts to the navy as it tries to balance the books.

While Admiral Sir Jonathon Band – who leaves his job next month – insisted he had seen 'no evidence' of fresh setbacks, he warned ministers in the next government not to delay the carriers again.

Speaking to The News at the launch of an aircraft carrier exhibition at Portsmouth's Historic Dockyard yesterday, he said: 'I don't need to tell you about the importance to the navy of the carrier programme.

'There's so much investment going on across the country and its value to Portsmouth is well-known.

'I have no evidence that the project is not going to get the support of the next government.

'But if Britain wishes to stay as a major power these ships are essential.'

Only last week Adm Band expressed concerns about what the government was asking the navy to do with a shrinking fleet.

He has also been at loggerheads with Sir Richard Dannatt, chief of the general staff, who branded the carriers 'cold war relics'.

Experts say Adm Band's comments were clearly directed at any new government which takes power in the next year.

Cdr John Muxworthy, chief executive of the United Kingdom National Defence Association, said: 'What he said last week and what he's saying on the carriers is absolutely right.

'There's no way you can expect Britain to maintain its prestige without backing it up with actions.'

And he added: 'As he comes to the end of his tenure he's starting to speak more directly on the issues, and our association hopes that he will stay on the national scene to make these points.'

HMS Queen Elizabeth and HMS Prince of Wales are planned to enter service between one and two years later than their planned dates of 2014 and 2016.


INTERACTIVE NEW EXHIBIT

Adm Band was at the launch of a new exhibit at Action Stations in Portsmouth Historic Dockyard. The Carrier Strike display is a series of interactive screens and games that let visitors get a view of what the carriers will be like.

Built by defence giant BAE Systems Insyte with the Aircraft Carrier Alliance partnership, it aims to give people a flavour of the technology involved.

On the current delay of the carriers, Adm Band said: 'It's inevitable with big projects that you get good and bad days, that you get money problems and the challenge of dealing with a huge amount of information.

'However I think the current dates for the carriers coming in are realistic, given we haven't built a big carrier for a long, long time. We've got the steel cutting in Glasgow next month, the engines have been ordered and there is a momentum building.'

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