Politicians at war over EU vote amid revelation membership's a £500m drag on Stormont
Cameron and Johnson lock horns in London while McGuinness and Allister clash back home as Europe debate heats up
The EU has been branded a £10m-a-week drain on Northern Ireland amid claims a vote to leave is the gateway to growth and prosperity.
Proportionally Northern Ireland's share of the UK's contribution to Europe is running at around £500m a year.
The astonishing cost emerged as Prime Minister David Cameron set out the case for the UK remaining in the EU.
Mr Cameron said the country faced a choice of becoming an "even greater Britain" or taking a "leap into the dark".
As the referendum battle gathered pace in London and Belfast:
- Mr Cameron launched a savage attack on Boris Johnson; accusing him of backing Brexit for his own leadership ambitions;
- Mr Johnson hit out at "scaremongering" by the 'In' campaign, saying the economic risks of leaving were "wildly exaggerated";
- Northern Ireland Secretary Theresa Villiers said calls for her to resign over her Brexit stance were "ludicrous";
- Former Chief Constable Sir Hugh Orde claimed quitting the EU would leave the UK more vulnerable to terrorism;
- Deputy First Minister Martin McGuinness warned the implications of Brexit would be "absolutely enormous" for Northern Ireland.
Yesterday TUV leader Jim Allister claimed Northern Ireland was losing millions every year through its membership of the EU.
He pointed to figures showing UK taxpayers pour £19bn into Brussels each year, but get back just a fraction.
In 2014 Treasury figures showed the UK contribution to the EU was £19.234bn. The UK rebate was £4.888bn and £4.539bn was paid out in EU grants.
Northern Ireland's proportionate share of the UK's annual contribution is around £500m.
Last year we got back £300m in funding for agriculture and £133m from EU structural funds - leaving a £67m shortfall.
Mr Allister, a strong EU critic, said: "There is the nonsense spun about Northern Ireland being unable to survive without EU handouts. Not only is it our own money we are getting back, but even we are net contributors.
"Prosperity and growth, along with the dignity of standing on our own feet and making our own decisions, await us outside the EU."
DUP MP Nigel Dodds said the UK pays in £1.58 for every £1 it gets back from the EU.
He told the BBC that a UK exit would mean a "lot more money available to the UK and Northern Ireland".
But Mr McGuinness warned of "enormous" implications of Brexit.
"Anybody that has examined our relationship in the north with the EU over the course of many years can't fail to recognise enormous benefits there have been for the community and voluntary sector, farmers and business community," he said.
It came ahead of a fiery Westminster debate where Mr Cameron and Mr Johnson came up against one another in the House of Commons for the first time since the London Mayor declared his support for Brexit.
In a lightly-veiled reference to Mr Johnson's apparent ambition to succeed him as PM, Mr Cameron said his own pledge to step down at the next general election meant he had "no agenda" other than the interests of Britain.
Making clear that a vote to leave would be followed by withdrawal negotiations under Article 50 of the Lisbon Treaty, Mr Cameron said: "Sadly, I've known a number of couples who have begun divorce proceedings, but I don't know any who have begun divorce proceedings in order to renew their marriage vows."
His comment was greeted by loud laughter from Labour MPs directed at Mr Johnson, whose own first marriage was dissolved in 1993.
Earlier, Mr Johnson hit out at "scaremongering" from the In campaign side. He said the economic risks had been "wildly exaggerated" by some in the City.
In a separate development, former PSNI chief Sir Hugh said it was "a fact" that the UK would be more vulnerable to attack if it exited the EU. "We have access to joint intelligence, shared intelligence," Sir Hugh said.
"We can export people through European arrest warrants, including terrorists who we catch in this country.
"We rely on Europol to share information, and of course Europol has now set up a specific operation to deal with the new terrorist threat.
"To step out of that would simply render this country far more vulnerable to terrorism, not less."
Concerns were also raised about European grants worth almost £425m to support peace in Northern Ireland.
Around £424m was announced last month and applications have already begun. The programme is due to end in 2020.
Yesterday, Downing Street poured cold water on the prospect of a second referendum if the UK votes to withdraw from the EU on June 23, insisting that "a vote to leave is a vote to leave".
The second referendum option had reportedly been floated by Mr Johnson as a means of securing further concessions from the EU.
"If the British people vote to leave, the Government will clearly respect the outcome of that," said the PM's spokeswoman.