Britain could be relegated from the top division of seafaring nations without a £1 billion investment in its fleet, the head of the Royal Navy cautioned yesterday.

First Sea Lord Admiral Sir Jonathan Band, who is expected to be the next Chief of Defence Staff, said that Britain would be at risk of “turning into Belgium” without extra funding to sustain its naval capabilities.

The admiral later insisted, in a statement released through the Ministry of Defence, that he was not criticising present funding levels and said that his remarks were designed to “inform the public debate”.

His comments come after a series of outspoken attacks on the Government’s defence policy by former and current army chiefs. Last year, General Sir Richard Dannatt, the Army’s most senior commander, caused a panic in Whitehall when he contradicted government policy on Iraq, saying that the continuing presence of British troops was exacerbating problems. He also said that his troops were “at the limit of their capacity”.

Sir Jonathan told his lunch guests that the extra investment was needed to maintain the Navy, which he described as a “special asset”, and to buy two new aircraft carriers.

He said: “If you want to use it, it doesn’t come for nothing. We’re at a scale now that requires a certain amount of investment to maintain. You can’t do deterrence unless you are a really professional outfit.”

He said that he had raised the issue privately with both the Prime Minister and the Chancellor, and summarised his position as “give me two carriers and just less than a billion and I will be off your back, a happy boy”.

The Conservatives said that the remarks were evidence that Gordon Brown was refusing to provide much needed cash for the Armed Forces.

Julian Lewis, the Shadow Defence Minister, said: “The fact that the First Sea Lord feels it necessary to speak out in this forthright way confirms everything we have said about the destruction of the frontline strength of the fleet.

“The 1998 Strategic Defence Review committed the Government to 32 frigates and destroyers. We are now down to 25, with possibly 6 more to be lost despite the fact we have since embarked on 2 major military campaigns.

“The Armed Forces are overstretched as never before. Whilst Tony Blair increases commitments, Gordon Brown again refuses to provide the resources necessary.”

Later, the admiral said in a statement: “I do not think, and have not said, that the Royal Navy needs £1 billion-a-year extra to do its job or to keep ships at sea.

“Today’s Royal Navy is funded to do what is asked of it, not least thanks to a current investment programme of £14 billion and the delivery of 28 new ships in the last decade alone.

“As the Prime Minister has said, if we as a nation are to extend what our Armed Forces can do, the public needs to feel comfortable with the economic choices needed to make that happen.

“I welcome the way the Prime Minister has started this debate, as I welcome the Government’s commitment to the new aircraft carriers.

“My comments today have been aimed at informing this public debate about the long-term funding of our Armed Forces, nothing more.”

Tony Blair said last month that Britain must maintain its status as a leading defence power, with military might essential to winning the war against terrorism.

“For our part, in Government, it will mean increased expenditure on equipment, personnel and the conditions of our Armed Forces — not in the short run, but for the long term,” he said in a speech delivered on board HMS Albion.

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