The Labor General Election manifesto was signed "unanimously" tonight after a meeting of party chiefs that lasted more than six hours.
The 'transformational' document is expected to promise nationalized mail, rail, water, energy and broadband, free NHS prescriptions and free six-year adult education in England and a £ 10 minimum wage for anyone over 16.
But unions and some of Labor's front benches were split ahead of a Clause V meeting on key issues – including immigration.
Moments after the meeting tonight it was still unclear what agreement was reached on freedom of movement after Brexit.
Several rows have also previously raged over the exact terms of the Green Labor deal for labor, union sources say.
The full manifesto will only be released on Thursday after its launch, after it was released in full in the 2017 Mirror.
Shadow office minister Jonon Trickett said the discussions were "very good", adding that they were "ready to go to war as soon as possible".
Shadow Brexit secretary Sir Cir Starmer said the meeting was "good", while many others refused to share details before the official launch.
Asemiemi Corbin said as the meeting ended: "We just had a very extensive meeting of the national executive of our party, the Cabinet of Shadows and other people as well.
"And we have reached a unanimous agreement on the content of our manifesto that will be released next week.
"That manifesto is a transformative document that will change the lives of the people of this country for the better.
"It will be an opportunity for a generation to suddenly vote for a more egalitarian society that cares about everyone and I'm very proud of the content and I can't wait to get that content and it's a promise of a better Britain for everyone across the country at a time of our election campaign. "
Asked if the manifesto was more radical than in 2017, Labor Party leader Ian Lavery said it was.
After leaving a central meeting in London, he told the BBC: ouz: "This is the best manifesto you'll ever see.
"I would like to tell you what was discussed and what the new policies were. They are very exciting and I look forward to seeing you all on Thursday when everyone is revealed.
"We sorted out all the problems and it was fantastic. Everyone was ready for it, very friendly, good discussions, good debate, very long because we have a great manifesto. "
Today's meeting was shrouded in secrecy as the present phones seized their phones to prevent leaks and were told to use a labor-protected emergency telephone.
One source indicated that shadow cabinet ministers had not even seen the final drafts of their departments.
Unlike the Tory manifesto, the work is being contracted by a shadow cabinet, the ruling NEC, PLP, Scottish and Welsh leaders and union representatives at a mammoth meeting ahead of Election Day.
Mr Corbin arrived at the protesters chanting "The Labor Party to hear us say – free movement here to stay" at 10.30am in central London.
The Labor Party's conference last month adopted a radical move to "uphold and extend the rights of free movement", "to secure the unconditional right to family reunification" and "to reject any income-based immigration system, a tool for migrants to do business and number of caps / targets ".
But party leaders have repeatedly pointed out the policy – for which false claims that the Tories are restricting all immigration controls – will not go unchanged in the manifesto.
A union source said the Mirror unions were also divided, with United and the CDU pushing for a tighter line, including protecting workers' rights, while TSA and Unison wanted more open policies.
The Clause V meeting was to be opened with an introduction by NEC President Andy Fox, followed by a presentation on the "political context" by Jeremy Corbin.
The manifesto was then due to be introduced at a time – including on the economy, the NHS, education, police, migration, housing and a second Brexit referendum.
Changes to the text can only be made if there is consensus, including Mr Corbin and the relevant shadow cabinet member. If that consensus does not exist, the question may be put to a vote.
The final manifest will then be approved for simple hands-on display.