For some months there has been a war in the Home Office between the Home Secretary (Priti Patel) and the top civil servant Sir Philip Rutnam, which has now been brought to a head by Rutnam's resignation and a potential Employment Tribunal for Unfair Constructive Dismissal. Priti Patel's Top Civil Servant Quits After 'Campaign Against Him' HuffPost UK revealed on Thursday that tensions had risen between Sir Philip Rutnam and Priti Patel after he refused to sack a colleague on Christmas Eve. By Sarah Turnnidge Peter Summers/Getty Images / Helen William/PA Philip Rutnam, the Home Office's most senior civil servant, has quit The Home Office’s top civil servant has quit after a “vicious and orchestrated campaign” against him. Sir Philip Rutnam said there had been an orchestrated campaign against him, and told the BBC that he planned to sue the government for constructive dismissal. In a statement published via the senior public servants’ union, the FDA, Rutnam said he had made the decision “with great regret after a career of 33 years”. “In the last 10 days I have been the target of a vicious and orchestrated briefing campaign,” he added. “It has been alleged that I have briefed the media against the home secretary. “This along with many other claims is completely false.” Sir Philip Rutnam’s statement in full: pic.twitter.com/aKQXicFeqp — FDA union (@FDA_union) February 29, 2020 He continued: “The home secretary categorically denied any involvement in this campaign to the Cabinet Office. “I regret I do not believe her. She has not made the effort I would expect to dissociate herself from the comments. “Even despite this campaign I was willing to effect a reconciliation with the home secretary. “But despite my efforts to engage with her, Priti Patel has made no effort to engage with me to discuss this. “I believe these events give me very strong grounds to claim constructive, unfair dismissal and I will be pursuing that claim in the courts.” On Thursday, HuffPost UK revealed that home secretary Priti Patel had wanted to move Andy Tighe, one of her most senior officials, out of the department on Christmas Eve and asked Rutman to deliver the news. Rutnam refused to do so, believing it too cruel to effectively sack his colleague on Christmas Eve, HuffPost UK understands. Rutnam’s refusal to carry out Patel’s orders is said to be one of the factors that has led to a breakdown in their relationship. Relations between the pair were said to have deteriorated to such a level that Patel has blacklisted her permanent secretary’s staff and is cutting them out of regular day-to-day meetings. Prior to Rutnam’s resignations there had been reports that Patel had demanded his removal. Sir Mark Sedwill, cabinet secretary and head of the Civil Service, said: “I have received and accepted with great regret the resignation of Sir Philip Rutnam. “I thank him for his long and dedicated career of public service. Shona Dunn, the second permanent secretary at the Home Office responsible for borders, immigration and citizenship, will become Acting Permanent Secretary with immediate effect. “The Home Office’s vital work to keep our citizens safe and our country secure continues uninterrupted.” Responding to Rutnam’s resignation, Dave Penman, general secretary of the FDA, said it “demonstrates once again the destructive consequences of anonymous briefings against public servants who are unable to publicly defend themselves,” and called on Boris Johnson to “put a stop to this behaviour”. He added: “This cowardly practice is not only ruining lives and careers, but at a time when the Home Office is being tasked with delivering a demanding government agenda on immigration, and preparing for a public health emergency, it has diverted energy and resource in to responding to unfounded accusations from sources claiming to be allies of the Home Secretary. “The FDA has supported Sir Philip throughout this period and will continue to support him in his claim for constructive dismissal. “He had a choice to resign and go quietly with financial compensation. Instead he has chosen to speak out against the attacks on public servants. “I know many thousands of his colleagues will recognise the courage and integrity he is showing in doing so and will applaud his decision. “The Home Office now needs to find new leadership at a time when it needs stability. “Those who engage in anonymous briefings need to bear the responsibility for this destructive behaviour. “Only the prime minister can put a stop to this behaviour and unless he does so, he will have to accept his own responsibility for the consequences.” Labour MP Stephen Doughty, a member of the Commons home affairs committee during the last parliament, has called on the Home Secretary to “explain herself” as soon as possible to MPs. In a tweet he called Rutman’s statement and resignation “utterly explosive”. “Chaos at the Home Office when it’s supposed to be delivering highly controversial policies,” he said. “It is vital that Priti Patel comes to explain herself at the Commons home affairs committee ASAP.”