"They have failed to accept that there were serious issues with the application system despite providing evidence that attempts of submission were made before the deadline. The NEC deny this is the fault of the Ukip system.
"Furthermore, highly confidential information about me held in party documents has been leaked to the press and the NEC has not sought to investigate this gross breach of privacy."
Three members of the party's NEC immediately resigned from the committee in protest over what they described as the "deliberate obstruction" of Mr Woolfe's nomination.
Victoria Ayling, Michael McGough and MEP Raymond Finch said the "escalating megalomania" of members of the board had been "detrimental to the functioning of the party".
The NEC "has essentially usurped full governance of the party" and is "collectively in pursuit of oligarchy, self-promotion and cronyism", they said.