London, March 1 (IANS): British Home Secretary Priti Patel was facing pressure to respond to bullying allegations made by Philip Rutnam, the Home Office's most senior official who resigned citing a "vicious and orchestrated" campaign against him, a media report said on Sunday.

While announcing his resignation on Saturday, Rutnam said that he received allegations that Patel's conduct towards employees included "swearing, belittling people, making unreasonable and repeated demands", the BBC reported.

Rutnam said that he now intended to take legal action against the Home Office on the basis of constructive dismissal.

Patel, who was yet to publicly respond to Rutnam's claims, has previously rejected newspaper reports that she mistreated staff.

Responding to the development, opposition Labour's Keir Starmer, a front-runner in the party's leadership race, said on Sunday: "The Home Secretary has a duty to come to Parliament on Monday to explain the allegations made about her own conduct."

He also called for the head of the civil service, Cabinet Secretary Mark Sedwill, to start "an immediate investigation" into the circumstances surrounding Rutnam's departure.

Meanwhile, shadow Cabinet Office Minister Jon Trickett called on Prime Minister Boris Johnson to make a statement.

Former head of the civil service, Bob Kerslake, suggested that the home secretary would have to resign if Sir Philip wins his legal action.

According to the BBC, allies of Patel were privately suggesting that Rutnam was not up to the demands of the job.

The Home Office has to deliver on two key election pledges - recruiting more police officers and swiftly introducing a new, post-Brexit immigration system.

Asked if the Prime Minister had full confidence in Patel, a Downing Street told the BBC that Johnson had full confidence in his cabinet.

Shona Dunn, who had been Rutnam's deputy, will become Acting Permanent Secretary.