Guardian/Observer March 2017.
"A hard-left plot by supporters of Jeremy Corbyn to seize permanent control of the Labour party and consolidate their power by formally joining forces with the super-union Unite can be revealed by the Observer.
The plans, described on Saturday by Labour’s deputy leader Tom Watson as “entryism” and a covert attempt by a leftwing faction to take over the party, were spelled out in detail by Jon Lansman, the founder of the grassroots organisation Momentum, who was secretly recorded addressing supporters at a meeting of a new branch of the organisation in Richmond, south London, on 1 March.
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On the tape, obtained by the Observer, Lansman issues a call to arms to Momentum supporters, saying they need to make sure the left is far better represented in key positions at all levels of the party so they have control over the levers of power when Corbyn departs and the succession is decided.
Most controversially, Lansman says that if his ally Len McCluskey secures re-election as general secretary of Unite in an internal election next month, the super-union will then link directly to Momentum by formally affiliating to it, in what critics fear would amount to a massive shift of power and financial resources to the pro-Corbyn left."

https://www.theguardian.com/politics/2017/mar/18/secret-tape-reveals-momentum-plot-to-link-with-unite-seize-control-of-labour