The security service has been dragged into the internal war between Priti Patel and her top civil servant as officials issued an unprecedented denial that the agency did not trust her with intelligence.
Unnamed sources were quoted at the weekend claiming MI5 officers had reduced the volume of intelligence they show to the Home Secretary because they did not have confidence in her abilities.
Sir Philip Rutman, the Permanent Secretary at the Home Office, is suspected by allies of Ms Patel of sanctioning briefings against her after she sought to have him removed following disagreements over his obstructive approach to her.
MI5 officers were said to be furious at the claims, published in The Sunday Times, and within hours security sources took the highly unusual step of issuing a denial unprecedented in its strength.
Reports suggesting that the Home Secretary and MI5 do not have a strong relationship are simply untrue, said a security source.
The Home Secretary is briefed daily on intelligence matters in exactly the same way as any previous post holder. No information is being withheld. Any report suggesting otherwise is simply wrong and does not serve the public interest.
It came as it also emerged Amber Rudd, the former Home Secretary, has filed a formal complaint, accusing Sir Philip of being absent during the Windrush immigration scandal that led to her resignation.
A Tory source said: It’s quite clear what’s going on here. Rutnam is attempting to discredit a Home Secretary who is shaking things up a bit to try and salvage what little is left of his reputation. You can’t blame him for trying given that he managed to throw Amber under the bus.
The disagreements went public last week when sources accused Ms Patel of bullying and belittling staff, claims denied by allies of the Home Secretary.
With little sign of the row abating, Ms Patel and Sir Philip attempted on Sunday night to draw a line under the affair with a joint statement, criticising the false allegations and malicious gossip and insisting they were focused on delivering the Governments agenda.
It came as one former insider claimed Sir Philip spends his time politicking rather than running the actual department.
You would sit in meetings with Rutnam and Priti would say: Where are you with this issue? and he would say: I will have to get back to you on that, they said.
He was allegedly so obstructive that he was nicknamed Dr No, because he just said: No, the source claimed. He was also known for quashing ideas by regularly claiming there was a 70 per cent chance of the Home Office losing a legal challenge or case.
The insider said the problem was a hangover from Brexit when officials ran rings round the politicians. Theres a clash now because of them being used to do it their way but suddenly no longer being able to operate that way because of the new regime, they said.
He is also old school. He got on with Sajid Javid but he had a problem with Amber and Priti. He doesnt get on with strong women who come in with their own views.
The Home Office also described as categorically untrue a claim in The Observer that major run-ins between Ms Patel and staff had forced the resignation of one of her departments most senior civil servants on immigration. It said the civil servant had resigned before Ms Patel became Home Secretary.