Home Secretary Priti Patel has expressed her concern at "false allegations" that she says are being made about her amid claims of bullying and distrust from intelligence chiefs.
An ally to the home secretary said she was "absolutely livid" about the recent slew of allegations and insisted she was demanding a leak inquiry to be carried out by the Cabinet Office.
Cabinet Office sources were adamant, however, that a request had not been received either formally or informally - exposing an apparent escalation of the row.
The Government on Sunday moved to strongly deny claims that MI5 chiefs do not trust Ms Patel and were limiting intelligence sharing.
The latest allegation came after the home secretary was accused of bullying officials and creating an "atmosphere of fear" at the department.
Allegations allies of Ms Patel deny.
It emerged last week the MP for Witham had tried to move permanent secretary Sir Philip Rutnam from her department after they had a series of rows.
On Sunday, a Home Office spokesman said: "The home secretary and permanent secretary are deeply concerned about the number of false allegations appearing in the media.
"They are focused on delivering on the Home Office’s hugely important agenda, which includes creating an immigration system that works for the UK, putting more police on the streets and keeping the public safe from terrorism."
The security services were dragged into the row when the Sunday Times reported officials alleging intelligence chiefs do "not trust" her and have decided to share less intelligence with her.
Responding to the reports, a Government spokesman said: "The home secretary and MI5 have a strong and close working relationship, and baseless claims to the contrary are both wrong and against the public interest.
"The home secretary receives the same daily intelligence briefings as her predecessors, and no information is being withheld."
An ally said Ms Patel asked the Cabinet Office’s director-general of propriety and ethics, Helen MacNamara, to carry out a formal leak inquiry. But added that Ms MacNamara has so far blocked the attempt.
This, however, was quickly denied by Cabinet Office sources who moved to say no request had been made to Ms MacNamara.
Home Office Minister James Brokenshire said Ms Patel is "demanding" but he does not accept claims that she is a bully.
Mr Brokenshire labelled the reports about Ms Patel "false" and said he "simply did not recognise the allegations and assertions being made".
The MP for Old Bexley and Sidcup said the Home Office was a "challenging" and "difficult" place to work due to the issues, such as terrorism and border control, that it deals with, and that Ms Patel had to be "challenging" in order to meet these demands.
He continued "public safety" was at the "forefront" of Ms Patel's mind and that she was committed to delivering the Government's agenda.
He added that the allegations being made against Ms Patel would not distract her or the Government from "the task at hand".
Tory former Cabinet minister Theresa Villiers said there was an element of misogyny in the briefings, telling BBC Radio 4’s Today programme: "I’m sick of spiteful briefings against women in high public office.
"It happens again and again and I don’t believe these allegations against Priti Patel.
"I think she’s a highly effective home secretary and I think whoever is making these briefings should stop it because I think they are unfair and they are damaging."
Meanwhile, Shadow Brexit secretary Sir Keir Starmer said the bullying claims suggested "something is going very, very wrong" in Ms Patel's department "and we need to get to the bottom of it because the Home Office is a very, very important department".
The Labour leadership hopeful added he did not "personally know how she has behaved", but the allegations suggested the "Government is really not functioning in the way that it should".
Asked about the claims that MI5 chiefs were limiting the information they give to Ms Patel, Sir Keir said it would be "very detrimental" if they were true.
The Holborn and St Pancras MP suggested both sets of claims should be investigated by the Home Affairs Select Committee.