Ed Miliband today branded David Cameron a "tainted prime minister" whose failure to stand up to the rich and powerful makes him unable to deliver the change which Britain needs.
Describing the Conservatives as "part of the problem", Miliband said the UK's return to recession has shown Cameron and his party to be tied to a set of outdated and ineffective economic, social and political orthodoxies which are "crumbling before our eyes".
As the prime minister prepares to attend the G20 summit in Mexico, Miliband said the world needs new economic leadership to deliver a global plan for jobs and growth.
He seized on evidence from the Leveson Inquiry of Cameron's close links with senior figures at News International, arguing that it shows him to be someone who stands up for "the wrong people".
In a speech to Labour's National Policy Forum in Birmingham, Miliband said his party's task is to "rebuild Britain" so it works for everyone, and not just a powerful and privileged few.
Describing the next steps in Labour's policy review, Miliband said it will focus on three themes: rebuilding the economy, rebuilding society and rebuilding politics.
He set out his "vision for our future economy", where companies would be regarded as a shared project between workers, management, shareholders and customers, with reduced pay inequality and an end to poverty wages.
Miliband said he wants to create a more equal society, built on "care, compassion and real reciprocity, not just on money, market and exchange".
Labour must restore confidence in politics by "standing up for the many against the interests of the few, however powerful they are", he told his party.
"The scale of the crisis we face is enormous," he added.
"The task we face is no ordinary task for an Opposition. It is certainly not the time to carry on as we did before. It is not the time to try to make do and mend.
"Our task will be to rebuild Britain. To rebuild our economy. To rebuild our society. To rebuild our politics. So that we can rebuild our country to ensure that it works for everyone, and not just a powerful, privileged few."
The Labour leader said the Leveson Inquiry into media standards has become "a symbol for what is wrong with our politics... a scandal about the way Britain is run in which unaccountable power was exercised by some newspapers".
He cited details from Cameron's appearance before Leveson on Thursday - including an email exchange with former News International chief executive Rebekah Brooks - to support his claim that the PM is "tainted" by his links with the rich and powerful.
"This is a Prime Minister who sent the texts, received the texts, even rode the horse," Miliband said.
"What we now know is we have a tainted prime minister. Tainted because he stands up for the wrong people. Tainted because he does not stand up to the rich and powerful. Tainted because he cannot be the change this country needs.
"When this prime minister says 'we're all in it together', he means country suppers with Rebekah Brooks. When we say we are all in this together, we are talking about the hard-working people of this country."
Responding to Miliband’s speech, Conservative Party Deputy Chairman Michael Fallon said: “Ed Miliband was a central figure in Gordon Brown’s old team that was known for briefing against a sitting Prime Minister, abusive behaviour and negative spin.
“Labour were just as close to the Murdochs and to try to score cheap points on this issue is rank hypocrisy.”
Miliband gave his approval to the Government's announcement on Thursday of a £100 billion lending boost to banks but said Cameron's austerity programme is failing.
"Yes, it's right to supply credit to our banks," he said.
"But it doesn't change the fundamental problem. Austerity is not working in Britain with a double-dip recession. Austerity is not working internationally.
"The Tories are not the answer because they are part of the problem. They are stuck with an approach to our country's economy, society and politics that simply does not work any more: a set of orthodoxies whose time is over, which are now crumbling before our eyes.
"The Tories stand up for the wrong people; they run our country with the wrong ideas; they are both out of touch and out of date."
Mr Miliband used the event to set out the framework for the party's policy development.
On the economy, policies should aim to ensure that no-one who works remains in poverty; all young people have the chance of a career; and Britain has a culture of pride in work and production.
Companies should be seen as a "shared project", where rewards are related to effort and there is a "bond between those at the top and those at the bottom", he said.
He called for a "society of shared responsibility", which is more equal and where public services treat people as "a valued partner, not just a customer or a number on a spreadsheet".
Miliband also said that Britain needs a politics where people feel that "every decision that affects them is made by someone accountable to them", with more devolution for English local government and proper representation of women, ethnic minorities and the working class.