In a sensational attack on the leader of the UK Independence Party, its former chief executive has said that Nigel Farage is causing the party to fail.
Will Gilpin, who quit earlier this week after just eight months in the job, said Mr Farage viewed the party as "being about him" and accused him of stubbornly refusing to loosen his grip on power, according to the Daily Telegraph.
Ukip's failure to adopt a more professional management system means it will remain "a bunch of enthusiastic amateurs having a good time", he warned.
"The thing I am most shocked by is that Nigel does his own thing without the party knowing where he is or what he is doing," he told the Telegraph.
"Nigel is a great orator and a useful man for the party, but you have to use him in the scope of the wider organisation, rather than thinking 'It's all about Nigel'.
"Nigel would see the party as being about him. The party is structured like a flying wedge, pushing Nigel forward."
Mr Gilpin, a former RAF pilot tasked with making Ukip look more professional, is said to have devised a plan for election campaigning, training for staff and candidates, and structures for developing policies.
However, he claimed he was blocked from making changes that would have made the leadership more accountable to members.
Party sources suggested earlier this week that Mr Gilpin struggled to adapt to working at a smaller organisation whose "DNA is individualistic".
Mr Gilpin said: "The leap from being a small group of people who have fun and do what they want to being a professional political party was too much.
"Nigel has to have less power. There is no way around it," he added.
"I left by mutual agreement in response to my dissatisfaction at the fact I was not being allowed to do the job I was hired to do, which was to professionalise the party."
Mr Gilpin warned that without internal reforms Ukip would struggle in the 2015 general election.
"The party has decided it likes things the way they are - so Ukip remains a bunch of enthusiastic amateurs having a good time, rather than the professional fighting team they could be," he said.
"Individually, they have the skills to make that happen, but that means working together, and that is not really happening."
He added: "They might still win some seats - but not as many as they would if they organised and structured themselves to make the most of what they have."