Ed Miliband borrowed a political philosophy from the Tories as he sought to position Labour as an inclusive “one nation” party.
The tradition of one nation conservatism stretches back to 19th century prime minister Benjamin Disraeli and was adopted by later senior Tory figures including Edward Heath.
But the doctrine, based on ideas of reducing the gap between the rich and poor and tackling social problems, fell out of favour under Margaret Thatcher who derided the "wets" in her party.
Mr Miliband is not the first Labour figure to seek to assume Disraeli's mantle - Tony Blair also laid claim to the one nation agenda as opposition leader.
Labour's 1997 manifesto declared: "I want a Britain that is one nation, with shared values and purpose, where merit comes before privilege, run for the many not the few, strong and sure of itself at home and abroad."
The phrase derives from Disraeli's 1845 novel Sybil, in which he described the rich and poor as "two nations between whom there is no intercourse and no sympathy; who are ignorant of each other's habits, thoughts and feelings, as if they were dwellers in different zones or inhabitants of different planets; who are formed by different breeding, are fed by different food, are ordered by different manners, and are not governed by the same laws".
In 1872 Disraeli, as Tory leader, spoke passionately about the need for the state to intervene to help the poor in an address at Manchester's Free Trade Hall - which stood around 100 yards from the stage where Mr Miliband set out his own version of the one nation agenda.
A source close to the Labour leader said Mr Miliband felt the "one nation" spirit was shown during the Second World War and in the years following the conflict, when Clement Attlee's administration rebuilt Britain, including the formation of the NHS.
"A one nation country is a country where people of all background can work together," the source said.