BBC: Foreign Secretary David Miliband has suggested the European Union should work towards including Russia, Middle Eastern and North African countries.
He said enlargement was "our most powerful tool" for extending stability.
In his first major speech on the UK's relationship with Europe, he said the EU would not become a "superpower" but should be a "role model" for the world.
It could be a "model power of regional co-operation" dedicated to free trade, the environment and tackling extremism.
He said the EU must "keep our promises to Turkey", adding: "If we fail.... it will signal a deep and dangerous divide between east and west.
"Beyond that we must keep the door open, retaining the incentive for change and the prospect of membership provides."
Mr Miliband made his address at the College of Europe in Bruges, Belgium, where Baroness Thatcher delivered her famous warning against "some sort of identikit European personality" almost exactly two decades ago in September 1988. EU 'should expand beyond Europe' (more)
Miliband EU speech in full
WATCH BBC VIDEO:
EU ‘must look beyond Europe’
By contrast:
Mark AlexanderBaroness Thatcher
First, may I thank you for giving me the opportunity to return to Bruges - and in very different circumstances from my last visit shortly after the Zeebrugge ferry disaster, when Belgian courage and the devotion of your doctors and nurses saved so many British lives.
Second, may I say what a pleasure it is to speak at the College of Europe under the distinguished leadership of its Rector, Professor Lukaszewski. The College plays a vital and increasingly important part in the life of the European Community.
Third, may I also thank you for inviting me to deliver my address in this magnificent hall. What better place to speak of Europe's future than in a building which so gloriously recalls the greatness that Europe had already achieved over 600 years ago?
Your city of Bruges has many other historical associations for us in Britain. Geoffrey Chaucer was a frequent visitor here. And the first book to be printed in the English language was produced here in Bruges by William Caxton.
Mr Chairman, you have invited me to speak on the subject of Britain and Europe. Perhaps I should congratulate you on your courage. If you believe some of the things said and written about my views on Europe, it must seem rather like inviting Genghis Khan to speak on the virtues of peaceful coexistence!
I want to start by disposing of some myths about my country, Britain, and its relationship with Europe. And to do that I must say something about the identity of Europe itself.
Europe is not the creation of the Treaty of Rome. Nor is the European idea the property of any group or institution. We British are as much heirs to the legacy of European culture as any other nation. Our links to the rest of Europe, the continent of Europe, have been the dominant factor in our history. For three hundred years we were part of the Roman Empire and our maps still trace the straight lines of the roads the Romans built. Our ancestors - Celts, Saxons and Danes - came from the continent.
Our nation was - in that favourite Community word "restructured" under Norman and Angevin rule in the eleventh and twelfth centuries.
This year we celebrate the three hundredth anniversary of the Glorious Revolution in which the British crown passed to Prince William of Orange and Queen Mary. Visit the great Churches and Cathedrals of Britain, read our literature and listen to our language: all bear witness to the cultural riches which we have drawn from Europe - and other Europeans from us.
We in Britain are rightly proud of the way in which, since Magna Carta in 1215, we have pioneered and developed representative institutions to stand as bastions of freedom. And proud too of the way in which for centuries Britain was a home for people from the rest of Europe who sought sanctuary from tyranny.
But we know that without the European legacy of political ideas we could not have achieved as much as we did. From classical and mediaeval thought we have borrowed that concept of the rule of law which marks out a civilised society from barbarism.
And on that idea of Christendom - for long synonymous with Europe - with its recognition of the unique and spiritual nature of the individual, we still base our belief in personal liberty and other human rights.
Too often the history of Europe is described as a series of interminable wars and quarrels. Yet from our perspective today surely what strikes us most is our common experience. For instance, the story of how Europeans explored and colonised and - yes, without apology -civilised much of the world is an extraordinary tale of talent, skill and courage.
We British have in a special way contributed to Europe. Over the centuries we have fought to prevent Europe from falling under the dominance of a single power. We have fought and we have died for her freedom. Only miles from here in Belgium lie the bodies of 120,000 British soldiers who died in the First World War. Had it not been for that willingness to fight and to die, Europe would have been united long before now-but not in liberty, not in justice. It was British support to resistance movements throughout the last War that helped to keep alive the flame of liberty in so many countries until the day of liberation.
Tomorrow, King Baudouin will attend a service in Brussels to commemorate the many brave Belgians who gave their lives in service with the Royal Air Force - a sacrifice which we shall never forget.
It was from our island fortress that the liberation of Europe itself was mounted. And still today we stand together. Nearly 70,000 British servicemen are stationed on the mainland of Europe.All these things alone are proof of our commitment to Europe's future.
The European Community is one manifestation of that European identity. But it is not the only one. We must never forget that East of the Iron Curtain peoples who once enjoyed a full share of European culture, freedom and identity have been cut off from their roots. We shall always look on Warsaw, Prague and Budapest as great European cities.
Nor should we forget that European values have helped to make the United States of America into the valiant defender of freedom which she has become. [Source: The Bruges Speech in full (more)]
The Bruges Group
