FURY erupted last night after a secret German plot to establish an EU-controlled military defence force emerged in Berlin.
Leaked draft proposals from Chancellor Angela Merkel's government set out details of a joint European command headquarters and widespread cross-border "sharing" of military units and equipment.
Insiders said the bombshell announcement of the plan had been delayed until after Britain's in-or-out EU referendum in an attempt to avoid inflaming Euro-sceptic sentiment among voters.
Anti-Brussels campaigners warned that Britain could eventually be forced to join the initiative if the country votes to remain in the EU in the crunch poll on June 23.
The move, which could undermine Nato, was also seen as fresh confirmation that the drive towards EU integration will be dramatically intensify after the crunch vote on June 23.
Former Cabinet minister Iain Duncan Smith, who was also been shadow defence secretary, said: "Unfortunately, this revelation is entirely unsurprising.
"If there's one thing we know about the EU, it's that it is engaged on a relentless project of ever deeper integration — and the establishment of a Euro army is an intrinsic part of that.
For the sake of this country's security and prosperity we must take back control and Vote Leave
Iain Duncan Smith
"What is alarming — and some might say shaming — is that the UK Government is currently lobbying the British people to agree to something that will involve surrendering control over national defence, to a Euro Army.
"The prospect of having our defence policy dictated by Brussels will be a huge concern to British troops — as well as the public at large — and makes a mockery of the claim that Britain is stronger in the EU.
"With the euro collapsing, and the visa free travel zone set to extend from the English Channel to the Syrian border, the Euro Army is not a project that anyone should sign up to.
"On the 23rd of June we have a once in a lifetime opportunity to get out of a Union that is changing and developing in dangerous and destructive ways — for the sake of this country's security and prosperity we must take back control and Vote Leave."
Tory backbencher Jacob Rees-Mogg said: "This shows where we are going and what the EU is really about.
"This is fundamental to the debate. The EU is developing and there is no vote for the status quo. An EU army is now clearly on the cards."
Ukip MEP and defence spokesman Mike Hookem said: “When you look at the command structures, logistics and forces already under EU command, it comes as no shock the EU commission has bowed to German demands for a combined EU army.
“While we have had the EU High Command, and many other staff structures for many years, we have seen a determined push towards real assets coming directly under EU command since Jean-Claude Junker became president.
“You only have to look at how slowly and quietly the armed forces of the Netherland's have been subsumed by the German armed forces to see the creeping reality of how the EU aim to take over military and security structures throughout Europe.
“It is typical of the EU to make these sovereignty threatening decisions behind closed doors, and then to gradually implement them before finally presenting the desired outcome as a fait accomplice to the people of Europe.
“And don't for one second think that the UK will have an opt out on this issue, as David Cameron and the traditional parties have neither the political will nor clout in Europe to defend our armed forces from becoming one part of a far-reaching European military structure.
“However, I find it totally duplicitous and cowardly that David Cameron and the EU don't have the guts to tell the British people of their true intentions before the referendum on 23rd June.
“This is an issue that not only affects our way of life but the very core of UK sovereignty. The only way to stop this disastrous amalgamation is for the British people to vote leave."
And Andy Smith, chief executive officer of the UK National Defence Association, said: "British participation in Nato is the mechanism by which we should continue to cooperate with our western allies in Europe and North America.
"Nato is the partnership for mutual defence — it is difficult to see what purpose there could be in an integrated EU defence force unless it is about subjugating the British navy, army and air force to European control.
"If this scheme is serious then it is a cause for great concern and one that should play heavily on the minds of British people as they ponder the choice before them in the EU referendum on 23rd June.
"Do we really want our service men and women, who enlisted in the armed forces to fight for Queen and Country, having to swear allegiance to the President of the European Union?"
The German government's draft proposals set out plans for gradual co-ordination of the defence forces of the EU's member states.
A leaked discussion document said: "German security policy relevance — also far beyond our country.
"Germany is willing to join early, decisively and substantially as a driving force in international debates…to take responsibility and assume leadership."
The document was due to be published at the beginning of June. Insiders in the Berlin government said the publication date had been postponed until July because of sensitivities surrounding the British referendum.
EU nations would be invited rather than obliged to join the cross-border initiative under the proposals. And Britain already has the right to opt out of EU defence policies.
But critics are concerned that the paper still exposes the drive towards integration at the heart of the EU project.
The paper called for "the use of all possibilities" under EU treaties to establish co-operation between willing member states.
It also called for a joint civil-military headquarters for EU operations, a council of defence ministers and better co-ordination of the production and sharing of military equipment.
"The more we Europeans are ready to take on a greater share of the common burden and the more our American partner is prepared to go along the road of common decision making, the further the transatlantic security partnership will develop greater intensity and richer results," the paper says.
The British government has firmly resisted attempts in the past to extend EU control over defence, arguing such a move could undermine Nato.
Yet a number of EU-led security operations have been carried out in recent years. Since 2003, 37 EU security missions have been carried out including attempts to stamp out piracy.
Pressure has been growing in Germany on Chancellor Merkel to lead the way in the drive for more integrated EU defence forces.
A recent document from the foreign affairs committee of the Bundestag, the German parliament, said: "The creation of a European army is a long way off, but it is a strategic ndcessity to pave the way towards it now."
Former defence secretary Liam Fox yesterday called the EU drive for closer military co-operation a "vanity project".
In a speech at the Royal United Services Institute, the senior Tory also hit out at other EU nations for failing to match the British commitment to spend at least 2% of national income on defence each year.
"As one of the few countries meeting its 2% Nato commitment, British taxpayers are paying a disproportionate share of continental European defence," he said. "Far from magnifying capabilities in the potential application of hard power, our partners are increasingly taking a free ride on our substantially greater capabilities.
"It is worth noting that the British and French budgets now constitute more than 50% of all defence spending of European continent."
Last month, the Daily Express exposed attempts to set up an EU defence force “by stealth" by merging German and Dutch armies and navies. The proposal was seen as the nucleus of an EU defence force.