Mr Blair resigned from the country's top post yesterday in his Sedgefield constituency after over a decade as prime minister. In his resignation speech, Mr Blair reflected on the past ten years which have seen the Iraq and Afghanistan conflicts, the 7/7 attack on London and the introduction of devolution to Northern Ireland.
"I may have been wrong, that's your call. But believe one thing, if nothing else: I did what I thought was right for our country," he told a room packed with some of his most ardent supporters.
Mr Brown, the prime minister's likely successor and fellow architect of New Labour over a decade ago, praised his "unique" and "enduring" time in office.
However it is thought Mr Brown will attempt to differentiate his style of leadership from that of Mr Blair. According to the Guardian Ed Miliband, close ally to Mr Brown, spoke of a new style needed in "winning back people's trust".
"There was a New Labour style that got us into power, which was about message, about being on-message," he said at a rally at the London School of Economics.
"That is a style that belongs to the 1990s, it doesn't belong to the 2000s; partly because people are more intelligent than they are often given credit for, and you need to level with them and talk to them honestly about the challenges and dilemmas you face."
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