Theresa May's closest advisers created a "toxic" environment in Downing Street and put forward "batshit crazy" ideas, according to a former aide of the Prime Minister.
Katie Perrior said 10 Downing Street operated in a "pretty dysfunctional" manner during the 10 months in which she acted as Mrs May's director of communications.
Ms Perrior suggested the PM should have broadened her circle of advisers beyond her joint chiefs of staff, Fiona Hill and Nick Timothy, when she moved across from the Home Office last summer.
She also claimed the atmosphere in morning meetings with Mrs May would be "terrible" if Ms Hill and Mr Timothy were present, with other officials believing they could not speak freely.
Asked if the pair bullied and badly treated Cabinet ministers, Ms Perrior told BBC Radio 4's Today programme: "I think so. I think there was not enough respect shown to people that had spent 20 years in office or 20 years getting to the top seat in government.
"I felt sending people rude text messages was unacceptable.
"I felt what the Prime Minister needs when you're going through a tough time like negotiating Brexit is diplomats, not street fighters. They really only know one way to operate and that's to have enemies and I'm sure I'm one of those this morning."
Asked if she was pushed out, Ms Perrior said: "No, I was probably only ever going to do two years.
"But at the same time I've got to say every month that went past I thought 'Well, brilliant, I've been hanging on for another month', because it was pretty toxic."
Ms Perrior also developed her thoughts on her time in Downing Street during a column in The Times, in which she said she saw Mrs May stand up to Ms Hill "only a handful of times".
After recalling one such moment over how to campaign during the Copeland by-election, Ms Perrior wrote: "Normally we would all sit there while Fiona would raise some batshit crazy idea and not say a word.
"This one clearly had the Prime Minister rattled."