Labour leader Ed Miliband will argue today that the whole of the United Kingdom needs to be involved in the debate over Scotland's potential independence.
Mr Miliband will say it is possible to celebrate being English as well as British and accuses those wanting the break-up of the union of having a "narrow view of identity".
But he will admit that Labour had been "nervous" to talk about English identity in the past while pressing ahead with constitutional change in other parts of the UK.
Aides said Mr Miliband's decision to deliver the speech in London underlines his view that the case for the union must be heard in England and Wales, as well as Scotland.
Mr Miliband will claim the Scottish National Party, led by First Minister Alex Salmond, is offering a "false choice" between being Scottish or British.
The Labour leader will also take aim at commentators in England like Top Gear presenter Jeremy Clarkson who "shrug their shoulders at the prospect of the break-up of the union".
He will say: "A narrow view of identity would mean concern for the young unemployed in Scotland does not reach Newcastle or that we in England would care less for the pensioner in Edinburgh.
"What a deeply pessimistic vision. It's a mistake wherever you find it. Having to say: Scottish or British, Welsh or British, English or British. I don't accept any of that. It's always a false choice."
The Labour government put in place the devolved institutions in Edinburgh, Cardiff and Belfast, but Mr Miliband will acknowledge the party's failure to engage with English identity.
He will say: "We in the Labour Party have been too reluctant to talk about England in recent years. We've concentrated on shaping a new politics for Scotland, Wales, and Northern Ireland.
"But some people in England felt Labour's attention had turned away. That something was holding us back from celebrating England too. That we were too nervous to talk of English pride and English character. Connecting it to the kind of nationalism that left us ill at ease.
"In the 1970s/1980s, the Union flag was reclaimed from the National Front. Since Euro 96, the flag of St George has been reclaimed from the BNP.
"But somehow while there is romanticism in parts of the Left about Welsh identity (and) Scottish identity, English identity has tended to be a closed book of late.
"For too long people have believed that to express English identity is to undermine the Union. At the same time we have rightly helped express Scottish identity within the Union.
"This does not make sense. You can be proudly Scottish and British. And you can be proudly English and British, as I am.
"Now more than ever, as we make the case for the United Kingdom throughout the United Kingdom, we must talk about England.
"There may be a temptation on the part of others to conjure a view of Englishness which does not represent our nation, a mirror image of the worst aspects of Scottish nationalism: hostile to outsiders, anti-Scottish, England somehow cut off from the rest of Britain, cut off from the outside world, fearful what is beyond our borders, our best days behind us.
"I don't think like that. I love the nation that we have."
Mr Miliband will draw on his own experiences to explain his personal identity.
"I am the son of a Jewish refugee. A Leeds supporter, from north London. A baseball fan.
"I am proud to lead the Labour Party. I am proud to represent the people of Doncaster North. I am proud to be English. And I am proud to be British too.
"To me, Britain is a country where it is always possible to have more than one identity. More than one place in mind when you talk of home."
The Diamond Jubilee, the Olympics and England's footballers competing in the European Championship showed the different allegiances of people in the UK.
"This is an incredible time to live in this country. A once in a generation summer," he will say.
"But these multiple allegiances, the flags, raise serious questions too. What does this summer say about the United Kingdom?
"What does it say about our identity as a people?
"That's why today, as we stand between the jubilee, the European Championship and the Olympics, I want to begin to reflect on who we are as a country."
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