Documents passed to the BBC suggest Jeremy Corbyn's office sought to delay and water down the Labour Remain campaign. Sources suggest that they are evidence of "deliberate sabotage". One email from the leader's office suggests that Mr Corbyn's director of strategy and communications, Seumas Milne, was behind Mr Corbyn's reluctance to take a prominent role in Labour's campaign to keep the UK in the EU.
One email, discussing one of the leader's speeches, said it was because of the "hand of Seumas. If he can't kill it, he will water it down so much to hope nobody notices it".
A series of messages dating back to December seen by the BBC shows correspondence between the party leader's office, the Labour Remain campaign and Labour HQ, discussing the European campaign. It shows how a sentence talking about immigration was removed on one occasion and how Mr Milne refused to sign off a letter signed by 200 MPs after it had already been approved.
The documents show concern in Labour HQ and the Labour Remain campaign about Mr Corbyn's commitment to the campaign - one email says "what is going on here?". Another email from Labour Remain sources to the leader's office complains "there is no EU content here - we agreed to have Europe content in it". Sources say they show the leader's office was reluctant to give full support to the EU campaign and how difficult it was to get Mr Corbyn to take a prominent role.Given Milne's sympathy for authoritarian leaders like Stalin and Putin, we should not expect him to be a supporter of liberal democratic institutions like the European Union.