Jeremy Corbyn will condemn the UK's role in a series of "disastrous" wars in the Middle East, including current operations against Islamic State, claiming they have increased the security threat to Britain.
The Labour leader will speak out against a "succession" of conflicts which date back 14 years - taking in current operations against the extremist group as well as the wars in Afghanistan and Iraq.
In a speech to Labour activists he will promise a "new and more independent" relationship with the world if he is prime minister and insist he can build a "coalition" of support to win the 2020 general election.
Despite his landslide win in the Labour leadership contest, Mr Corbyn had little support amongst his colleagues in Parliament.
In a sign that he wants to increase his hold over the party's policies, he will stress his desire to give the grassroots members and supporters who elected him a greater say over Labour's future direction.
Mr Corbyn will use his strongest language yet to condemn the UK's involvement in the fight against Islamic State in Iraq, linking it to the wars begun in 2001 in Afghanistan under Tony Blair's premiership.
He has previously said that the UK should "look again" at its participation in the bombing campaign against IS.
But in a speech to Labour's East of England conference he will say: "For the past 14 years, Britain has been at the centre of a succession of disastrous wars that have brought devastation to large parts of the wider Middle East.
"They have increased, not diminished, the threats to our own national security in the process."
Mr Corbyn will call for "a different kind of foreign policy -- based on a new and more independent relationship with the rest of the world".
He will confront claims that he is unpatriotic, claiming Labour stands for the UK's "greatest traditions" including the suffragettes, the Beatles and Enigma codebreaker Alan Turing.
"What's pro-British about a Government that slashes support for serving soldiers and military veterans? How is it patriotic to take money from the poorest, from working families, and hand control of your country to a super-rich elite?
"Labour will take no lectures in patriotism from the Conservatives, the political wing of the hedge-funds, the bankers and the 1%?
"How dare Cameron's Conservatives pretend that they speak for Britain. We stand for this country's greatest traditions: the suffragettes and the trade unions, the Britain of Mary Wollstonecraft, Shelley, Alan Turing and the Beatles - and perhaps our greatest Olympian Mo Farah - the working people of this country who fought fascism, built the welfare state and turned this land into an industrial powerhouse."
In an indication that he wants to give his supporters in the grassroots a greater role, Mr Corbyn will insist he does not want "sectarian battles" or the settling of scores within Labour.
Setting out a desire to open up Labour's decision-making to the "hundreds of thousands of new members and supporters that have joined us since May" he will say: "It's a huge opportunity for Labour: to remake our party as a real social movement, organising and rooted in our communities.
"That's not about fighting sectarian battles or settling political scores. It's about opening up to the people we seek to represent and giving them a voice through our organisation and in our decision-making, and drawing individual and affiliated members into political action."
Mr Corbyn will acknowledge that Labour's failure to win back economic credibility or offer a "genuine alternative" cost them in May's general election.
He will insist: "If we focus everything on the interests, aspirations and needs of middle and lower-income voters, if we demonstrate we've got a viable and credible alternative to the Government's credit-fuelled, insecure, two-tier economy, I'm convinced we can build a coalition of electoral support that can beat the Tories in five years' time."
This will involve calling for a "break with the failed economic orthodoxy that has gripped the establishment in this country and others for decades", with a focus instead on state investment.
"We want to see the re-industrialisation of Britain for the digital age, driven by a national investment bank as a motor of economic modernisation for the 21st century, not the phony Northern powerhouse of George Osborne's soundbites and platform speeches - but a real economic renaissance of the north: a renaissance based on investment in infrastructure, transport, housing and technology that provides a solid return - but that this government prefers to spend on cuts in inheritance tax for corporate giants and the wealthy."
He will add: "Only an economy that is run for the real wealth creators and puts them in the driving seat - the engineers, the web designers, the cleaners, office and supermarket workers, technicians and health workers, as well as the entrepreneurs and the growing army of self-employed - is going to deliver prosperity for all in the future."