Image caption Mr Brown said it was a "delusion" to say exiting the EU wouldn't have financial consequences

Leaving the European Union would make Britain the North Korea of Europe with "few friends [and] no influence", Gordon Brown has warned.

The former Labour prime minister said the UK would be "out in the cold" if it withdrew from the 28-member bloc.

David Cameron has promised an in/out referendum on Britain's membership of the EU if the Conservatives win in May.

The Conservatives said comparing the UK to North Korea showed a "perverted sense of reality".

Speaking in an adjournment debate in the House of Commons, in what is likely to prove his last speech in the Commons before he steps down in May, the former prime minister said the government's stance had marginalised Britain in the EU.

'Culture war'

Addressing MPs, Mr Brown said he acknowledged the "strength of anti-European sentiment" in the country but argued that it was a "delusion" to believe that "retreating" from Europe would not have serious economic repercussions.

He suggested the right in British politics had launched a "culture war" over the issue of Europe and immigration which needed to be challenged, specifically the argument that "to be patriotic we must reject Europe in favour of Britain".

"Our destiny can never be to be some bit player on somebody's else stage," he said. "The England that glories in isolation is not the England I know and love."

Mr Brown said the UK was "weaker than ever" in the EU and had been fringe players on international issues such as the Greek crisis, climate change and Ukraine.

Under Mr Cameron's plans, the referendum on the EU would take place in 2017 after a period of renegotiation of the UK's terms of membership.

Labour has said it would not offer such a referendum unless there was a significant shift of power away from London to Brussels.

'True patriotic course'

Writing earlier in the Guardian, Mr Brown said: "We must tell the truth about the three million jobs, 25,000 companies, £200bn of annual exports and the £450bn of inward investment linked to Europe; and how the 'Britzerland' or Norwegian alternatives (even Norwegians oppose the Norwegian option) leave us subject to EU rules, but denied a vote in shaping them.

Image copyright Getty Images Image caption Mr Cameron has pledged to renegotiate the terms of Britain's EU membership and put it to a public vote

"And we must talk about how the Hong Kong option - 'leaving Europe to join the world' - is really the North Korea option, out in the cold with few friends, no influence, little new trade and even less new investment."

He said the UK was on course to overtake Germany as Europe's biggest economy in a decade, and it would not make sense to withdraw from the bloc now.

"It would be a terrible irony if Britain opts out, leaving Europe divided, Russia empowered, the US bypassing us for a Franco-German axis - and Scotland threatening to abandon a non-European UK."

The Kirkcaldy and Cowdenbeath MP argued that Britain's future lay within the European Union, saying it was the country's "true patriotic course" to lead it.

Hyperbole?

Replying for the government in the Commons, Business Minister Matthew Hancock said UK would maintain its influence through the "steadfast pursuit of our national interest" rather than "subordinating our goals" within those of a supranational organisation.

He said it was right that the British people had the final say on the UK's future in Europe.

Mr Brown's remarks have been met with criticism by some commentators, in particular his comparison between the UK and North Korea.

John Rentoul, Independent on Sunday columnist, said Mr Brown had weakened his argument with "exaggeration".

But the New Statesman's political editor, George Eaton, said that beyond the hyperbolic North Korea comparison "there is much wisdom" in the former PM's argument.

Mr Cameron wants to renegotiate Britain's membership of the EU if he remains prime minister after May, to win back powers in areas such as welfare and immigration - and put it to a public vote.

Labour has said the prospect of an EU exit is creating uncertainty and risk for British businesses.

The party has said it will only sanction a referendum if further powers are handed from the UK to Brussels requiring a fundamental change to existing treaties.

The Liberal Democrats remain committed to staying in the EU, while the UK Independence Party wants Britain to leave.