The 'remain' campaign has been hit with a bombshell claim after reports of secret plans to form an EU army emerged on the morning of 27 May. The blueprint is apparently being drawn up by Brussels and is being kept from UK voters until after the 23 June vote (EU referendum live blog: follow here).

The plans include new European military and operational structures and the EU's foreign policy chief, Federica Mogherini, has apparently spent a year and a half preparing the defence document for a 28 June summit, The Times reports.

The UK vetoed a similar plan in 2011 and the government has insisted that Britain would never become part of an EU army. But the report is likely to infuriate Brexit campaigners, who have previously warned about Brussel's alleged ambitions for an EU army.

A spokesperson for Britain Stronger in Europe said: "If we leave the EU, they could create a European army as we would not be at the table to veto it.

"The former heads of Nato, MI5 and MI6 have all said our country's national security is threatened if we leave. That's why we're safer remaining in Europe."

However, former defence secretary Liam Fox claimed a 'leave' vote would be the UK's "last chance to be dragged" into a permanent EU army. The report comes after a number of former British generals threw their support behind a Brexit, amid claims from remain campaigners that staying inside the EU would make the UK safer.

General Sir Michael Rose, a former SAS commander, said: "Sovereignty and defence are indivisible. European law, in my view, has already seriously undermined the UK's combat effectiveness as a result of the intrusion of European law into national law. And today, our servicemen and women are in danger of becoming no more than civilians in uniform."

The latest online opinion poll from BMG Research, of more than 1,600 people between 20 and 25 May, put leave one point ahead of remain (45% versus 44%).

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British Army personnel
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