Ed Miliband stakes his claim to be the next prime minister by claiming Labour are now the "one nation" party, in his big conference speech.
The Labour leader borrowed a political philosophy from the Tories, one that stretches back to 19th century prime minister Benjamin Disraeli and was adopted by later senior Tory figures including Edward Heath.
The doctrine is based on the idea of reducing the gap between the rich and poor and tackling social problems.
Mr Miliband said: "I didn't become leader of the Labour Party to reinvent the world of Disraeli or Attlee but I do believe in that spirit, that spirit of one nation.
"One nation: a country where everyone has a stake. One nation: a country where prosperity is fairly shared.
"One nation where we have a shared destiny, a sense of shared endeavour and a common life that we lead together.
"That is my vision of one nation, that is my vision of Britain, that is the Britain we must become."
Mr Miliband said his first step in delivering a One Nation economy would be to issue a warning to the banks that if they refused to separate their high street operations from the "casino", Labour would legislate to force the change.
He told delegates: "This is not just necessary to prevent another crisis but to do what has not been done for decades, enable us to pay our way in the world.
"We need banks that serve our country, not a country that serves its banks.
"Of course, this Government promised change but things aren't really changing. So I've got a message for the banks.
"We can do this the easy way or the hard way."
Mr Miliband set a deadline of the 2015 general election for banks to institute their own separation in their operations.