The deputy Labour leader Tom Watson faced a backlash from his boss after claiming the party was subject to infiltration by "Trots".

Jeremy Corbyn's campaign called his allegations "disappointing" and accused him of "peddling baseless conspiracy theories".

So Watson decided to hit back.

In a letter to the Labour leader, he declared: "It's not a conspiracy theory to say that members of these organisations are joining Labour. It's a fact."

More intriguingly, Watson quoted a document, which he said were being circulated by members of the grassroots organisation Momentum with links to far-left parties, and "goes against all the reforms we have been discussing... this year".

The instructions are in fact a description by a reviewer, Progress director Richard Angell, of the methods used by the faction Militant in the 1980s, as summarised by Michael Crick in his book on the subject. Angell characterises Militant as trying to make meetings as boring as possible to "reduce the sensible types".

Neither Crick nor Angell are Militant fan boys, but nevertheless, according to Watson some on the hard left have embraced the lessons in full.

Momentum has distanced itself from the document. A spokesman said: "We are not aware of the document that Tom Watson refers to in his letter.

"The description quoted from Michael Crick’s book runs entirely contrary to Momentum’s ethos and ways of organising."

Nevertheless, it's quite a strategy. Here are the instructions in full:

How to take control of Labour party meetings.

First, make the meetings boring. Flood the branches and constituency meetings with procedural requests, the minutes of the last minute and process.

This turns off the faint-hearted. Those with better things to do - attend to their family, careers or community groups - simply no longer turn up.

Part two: make the event adversarial. Uncomradely questions to sitting councillors and the MP, challenging the chair's method and motive, defining the politics of the speaker before they have defined their own - all these things to become the norm.

This behaviour basically reduces the attendance of the remaining sensible types. Then the meeting [is] ours to control.

Now for the piece de resistance. Once the troublesome moderates - organised or otherwise - are out of the way, motions and debates on policy and political positions will commence. Each will pass almost by acclaim.

No need for speeches against.If there is, allow it to be taken by the pantomime villain from the rump of "Labour right" attending membership.

Fromo here on it will be easy and the minutes often reflect the result of debates as "unanimous".

Subsequent speeches at Labour gatherings - Labour party conference and the like - will then be narrated with how much support they got at constituency Labour party level.

As for Michael Crick? That bourgeois capitalist has seized the opportunity to publicise his book (you can buy it here).

After Tom Watson challenge to Corbyn, read how Trotskyist Militant tendency infiltrated Labour, in my reissued book pic.twitter.com/FWXKvSigUj — Michael Crick (@MichaelLCrick) August 10, 2016

This article was updated on 25 June 2018 to make it clear that the instructions were a summary of the description in the book.