Prime Minister David Cameron warned Monday that a British exit from the EU would threaten peace on the continent, as the campaign for next month\’s crucial referendum gathered steam after regional elections.
With polls showing the "Remain" and "Leave" campaigns neck-and-neck, Cameron and former London mayor Boris Johnson, the "Leave" movement\’s de-facto leader, clashed as they stepped up their efforts to woo undecided voters.
A vote to exit the 28-member bloc in the June 23 referendum would be a "reckless and irresponsible" risk to Britain\’s economic stability that would leave it "permanently poorer", Cameron warned.
He also said a "Brexit" would threaten Britain\’s strength and security in the world, along with peace on the continent if "Europe\’s foremost military power" quit the European Union.
"Isolationism has never served this country well," Cameron said in a speech at the British Museum in London.
"Whenever we turn our back on Europe, sooner or later we come to regret it. We\’ve always had to go back in, and always at a much higher cost."
Cameron said that while Europe had largely been at peace since the end of World War II, it was barely two decades since the Bosnian war, while the continent was facing a "newly belligerent Russia", with conflicts in Georgia and Ukraine.
British war graves on the continent "stand as silent testament to the price this country has paid to help restore peace and order in Europe", he said.
"Can we be so sure that peace and stability on our continent are assured beyond any shadow of doubt?
"Is that a risk worth taking?
"I would never be so rash as to make that assumption."
But Johnson hit back at Cameron\’s warning, saying NATO had guaranteed the peace in Europe, not the EU.
"I don\’t think the prime minister can seriously believe that leaving the EU would trigger war on the European continent," he said at a speech in London, condemning "scare stories about World War III, or bubonic plague or whatever".
He said Brexit was now the "great project of European liberalism", and the EU an "obscurantist and universalist" 1950s project "well past its sell-by date".
Johnson attacked three "wholly bogus… myths" that EU membership boosts the economy and helps preserve peace, and that wanting to quit was anti-European.
Free from the London mayoralty, Johnson is the bookmakers\’ favourite to become the next Conservative leader and Britain\’s next prime minister.
The Conservatives are deeply divided over the EU referendum with only around half of its MPs joining Cameron in the Remain camp.
The prime minister insisted Monday that the party would be able to heal its rifts following the vote.
The "Remain" and "Leave" camps are locked on 50 percent each, according to the What UK Thinks website\’s average of the last six opinion polls.
The referendum campaign was picking up pace again after regional and local elections last Thursday which saw Labour\’s Sadiq Khan elected as London\’s new mayor, and pro-independence nationalists returned to power in Scotland, albeit without a majority.
Main opposition Labour leader Jeremy Corbyn was now being urged to get more involved in the EU referendum campaign.
Liberal Democrat leader Tim Farron said Corbyn was showing "half-hearted" support for the Remain cause, having "made a single speech and then retreated to his usual indifference".
Meanwhile Moody\’s credit rating agency said Brexit would see a "negative impact" on Britain\’s public services.
It said Brexit would lead to "heightened uncertainty" and slower economic growth, resulting in a possible downgrade to Britain\’s sovereign credit rating.