Foreign Secretary David Miliband has warned Labour it needs to show it is excited, not exhausted, by the prospect of a fourth term in government.
Mr Miliband will say goals need to be achieved in new ways
Mr Miliband told the Fabian Society that Labour can win the next election if it offers more change and more experience than the Tories.
He also signalled a break with Tony Blair's leadership by saying Britain is not a bridge between Europe and the US.
Instead, he said, it can act as a "global hub", linking world "networks".
'New ways needed'
BBC political correspondent Carole Walker said Mr Miliband appeared to be acknowledging how hard it is for Labour under Gordon Brown to present fresh appeal to the public.
He used his speech to warn the central challenge facing the party is "to show that we are excited, not exhausted, by the prospect of a fourth term in government".
He also said that the government needs to pursue its goals in new ways at home and abroad.
In a clear break with Mr Blair's approach, Mr Miliband said: "Britain is not a bridge between Europe and America: it can instead be a global hub, plugged into the networks that matter."
Our correspondent said this is not just a reference to the growing importance of China and India, but also to what Mr Miliband sees as the need to recognise a "civilian surge" - the rise of better-educated and informed citizens who want more power over their lives.
Mr Miliband said: "I know why we talked about being a bridge between Europe and America. Because they were talking past each other.
"But France and Germany now have good relations with America. That is good, but bridge was never quite right. We have global assets. A global language. Global businesses and NGOs. And global networks.
"That is why I talk about Britain as a global hub, promoting our values and interests on the global stage.
"We are members of the EU. Our most important bilateral relationship is with the US. And in China and India, our links with Europe and America help us do that."
Mr Miliband went on to emphasise that globalisation has brought internationally shared interests and problems.
He said: "From climate change and health pandemics to financial stability, national security comes not at the expense of other nations but in parallel.
"The challenge is to find ways to co-operate rather than compete, mobilising collective action in a world where power is more dispersed between nations, businesses and people.
"This civilian surge embodies the ideal of progressive politics, for what is progressive politics if not the desire to see more people as actors rather than spectators in life's dramas?
"Progressives can speak to this condition - but only by fusing rather than choosing between social democratic commitment to social justice through collective action and radical liberal commitment to individual freedom in a market economy."
In July last year Mr Miliband insisted the US would continue to be the UK's most important partner.
His assertion came after comments from two other ministers seemed to hint at a cooling of relations with the US.
Mr Miliband said issues such as climate change and terrorism could only be tackled with the US.
He gave the keynote speech at the Fabian Society's Change the World conference.