Labour's manifesto officially confirmed after embarrassing leak to press

Party leaders agree 51-page document after hours of wrangling over wording

Jeremy Corbyn claimed the party's manifesto would be 'very popular' with voters (Dinendra Haria)

Labour’s election manifesto has been “unanimously” agreed after the party held its “Clause V’ meeting that, according to its rules, must take place to sign off its plan for government.

The gathering, held at the Institute of Engineering and Technology in Westminster, took place after the entirety of the draft manifesto had been leaked to media the night before.

Party officials had gone to great lengths to keep the document secure; even shadow ministers had not been shown anything more than the pages relating to their policy briefs.

The leak led to an eruption of speculation and finger-pointing but, despite the animosity and continued hostilities between Jeremy Corbyn’s office and staff at the party’s headquarters, the meeting was calmer and more professional than some expected.

The shadow cabinet, National Executive Committee (NEC), representatives of the Parliamentary Labour Party and members of the party’s National Policy Forum were all present, along with members of Mr Corbyn’s team, with around 70 people said to have attended.

While the leak was mentioned, particularly by Jeremy Corbyn, who called for an investigation into who was responsible for it, and Shadow Foreign Secretary Emily Thornberry, the issue did not dominate discussions and those present were surprised by the extent to which it was put to one side.

“It was actually much calmer and more productive than I expected,” said one person present.

The discussion lasted for almost four hours and saw a number of changes made to the draft that, by the time of the meeting, had already been comprehensively documented in the media.

One source at the meeting described the changes made to the text, which was prepared by Mr Corbyn’s policy chief, Andrew Fisher, as little more than “tinkering”.

A senior party source confirmed that “nothing fundamental’ had been altered and said most of the changes had been clarifications and edits to phrasing.

The biggest sticking point was fracking, after representatives of the GMB union demanded the party’s opposition to the practice to be softened. They later backed down in the face of opposition from Labour figures concerned about the environmental impact of drilling for shale gas.

Concerns were also raised about a paragraph on Israel that criticised the Jewish state and mentioned it alongside Syria and Yemen in the context of “humanitarian crises”. Sources said some at the meeting wanted the text broadened to include reference to other countries and conflicts – an amendment that was approved.

At one stage Ian Lavery, Labour’s joint campaign chief, said he believed the polls were wrong and suggested that, to quote one source, “everything would be fine”. The claim was met with laughter from some in the room.

After the meeting, Mr Corbyn addressed reporters and announced that the manifesto had been “unanimously agreed”.

“We’ve amended the draft document that was put forward in the most informed, interesting, sensible discussion and debate in our party,” he said.

“Our manifesto will be an offer that transforms the lives of many people in our society and ensures that we have a government in Britain on 8 June that will work for the many not the few…We believe the policies in it are very popular.”

Reporters demanding to know whether the Labour leader had leaked his own manifesto and whether the whole episode constituted a “shambles” were studiously ignored.

Overlooking the fact that its contents was already splashed all over the nation’s newspapers, Mr Corbyn said the 51-page manifesto would be published “in the next few days” and promised “costings of all the pledges and policies that we make”. The leak, however, means the scheduled announcements are likely to be largely redundant.

Despite this, the Labour leader’s positive tone was echoed by Unite general secretary Len McCluskey, who described the meeting as “brilliant” and said there had been “complete unanimity” over the contents of the manifesto.

When NEC members began to emerge from the building, Mr Corbyn’s media team light-heartedly warned waiting journalists to mind their feet – desperate to avoid any other members of the media pack being injured in the course of following the Labour leader.

As the meeting drew to a close, a party spokeswoman announced that Mr Corbyn would be making a statement but would not be taking questions. In the end he emerged earlier than expected, spoke for two minutes and headed back into the building as reporters yelled questions about whether his office had been behind the leak.

The leaking of the manifesto had shattered the carefully-constructed plans for launching the party’s keystone policies and set the ball rolling on a surreal day that saw Mr Corbyn’s car run over a cameraman’s foot and Mr McCluskey emerge from the crunch meeting only to fall over and slide down the steps outside the building on his backside.

That incident sparked a row between reporters and the venue’s security staff, with the burly guards accusing the waiting media of “intimidating” Mr McCluskey, the controversial six-foot-plus leader of Britain’s biggest trade union and a man who is no stranger to the limelight.

As the recriminations over the leaked document continued, allies of Mr Corbyn accused staff at the party’s headquarters in Victoria of being behind the act in an attempt to destabilise the leadership, while others speculated that the leader’s office could have intentionally leaked their own document in order to frame his opponents and make it harder for the contents of the manifesto to be altered at Thursday’s meeting. Mr Corbyn’s team said such a suggestion was “categorically and completely untrue”.