A toxic culture, poor leadership and equally poor organisation were behind the Labour Party’s disastrous defeat at the General Election.
The damning verdict comes in a report by Labour Together.
The group, made up of MPs, party members, union leaders and the media, said the rout was “a long time coming”.
The no nonsense study identifies why Labour suffered its worst election results in 85 years.
It said the party “has a mountain to climb” to win the next election.
The report said that under Labour leader Jeremy Corbyn the party was “unprepared” for an election.
Labour had no “clear message” and tried to deliver a manifesto many thought undeliverable.
It said: “There is a broad consensus across the Party – mirrored in the results from the survey of Labour members – that a combination of concerns about the leadership, Labour’s position on Brexit and Labour’s manifesto not being seen as deliverable damaged Labour’s chances in the election.
“The Commission concludes that the weaknesses going into this election were interlinked, and indivisible.
“They catalysed long term trends between Labour and its voter coalition.”
The report also said concerns about Mr Corbyn’s leadership were “a significant factor in the election loss in 2019”.
It added: “‘Stop Jeremy Corbyn’ was a major driver of the Conservatives’ success across all their key groups including previous non-voters, and among all the swing voters Labour lost to the Tories.
“The very low poll ratings on leadership going into the 2019 election cannot easily be disentangled from the handling of issues like Brexit, party disunity and anti-Semitism.”
The group said divisive parts of the Labour organisation had failed to “present a united front to the public”.
It said: “Our Party has spent substantial periods of the last five years in conflict with itself resulting in significant strategic and operational dysfunction, resulting in a toxic culture and limiting our ability to work effectively.”