LONDON — British Prime Minister Boris Johnson’s controversial chief aide Dominic Cummings has left Downing Street after losing a power battle, with many saying that the latter leaves behind only a tempest of loathing and dysfunction. A Tory MP former Brexit secretary David Davis did not hold back on BBC Breakfast, stating that Cummings relationship with the PM ‘fell off a cliff’. Asked why Cummings left Downing Street, he cited reports of Carrie Symonds and new spokesperson Allegra Stratton as having “turned against him”, adding: “The relationship with the Prime Minister fell off a cliff. And once that"s gone, it"s gone.” Cummings’ resignation follows the exit of another top aide of Johnson, director of communications Lee Cain, who resigned on Thursday. Following Cain’s departure, Davis said the PM “needs a good chief of staff” — who he clarified would be “somebody who will be fiercely efficient, but not fiercely political, and that"s a difficult combination”. With Johnson reportedly keen to “clear the air and move on”, Tory MPs and peers voiced their hopes for a more “unifying” and “harmonious” leadership, with one accusing No. 10 of having “sidelined” both parliament and the Cabinet. With the former Vote Leave tactician’s departure raising suggestions of a less combative UK approach to Brexit trade talks as they enter their final stages, however, Brexiteers hoped a softer approach would not extend to the EU, with Nigel Farage quick to claim the events herald a “Brexit sell-out”. The former Labour spin doctor Alastair Campbell appears to have a similar outlook to the EU’s Guy Verhofstadt in warning of the “damage” Dominic Cummings leaves behind. “This is the tragedy of all this. This crowd secured the biggest change to our country in generations,” Alastair Campbell wrote in the Independent. “Yet they cannot even manage themselves, let alone the vast complexity of the change for which they are responsible. Britain, not they, will pay the price.” Noting the irony of the euroskeptic’s disdain for unelected bureaucrats, Verhofstadt also gave the more somber assessment that “the legacy called Brexit is damage that unfortunately will not be undone for years”. The departure of Cummings and Cain comes as the government grapples with the coronavirus pandemic, and as trade talks between the UK and the EU on their future relationship reach a "make or break" point. Labour said the PM could "rearrange the deckchairs all he wants... but the responsibility for this government"s incompetence still lies firmly at Boris Johnson"s door". "The fact there is no plan and no focus in the government"s response to COVID is entirely down to him," a party source said. Cummings had a notoriously difficult relationship with Conservative MPs, some of whom have said it is time for things to be done differently in Downing Street. Former Tory leader Sir Iain Duncan Smith wrote in the Daily Telegraph that Cummings" influence had led to "a ramshackle operation in the hands of one man". Another MP said was it was time to "rejoice" at the departure of the two aides, the BBC"s deputy political editor Vicki Young reported. Lord Gavin Barwell, who was former Prime Minister Theresa May"s chief of staff, told BBC Radio 4"s Today program there was an opportunity for Johnson to rebuild relations with Conservative MPs and "set a less confrontational and more unifying tone that is maybe more in tune with his natural instincts". And former Northern Ireland secretary, Theresa Villiers, said: "Both Dominic Cummings and Lee Cain were pretty dismissive of backbenchers and sometimes ministers and secretaries of state, and I don"t think that was helpful. "I do think it"s important that whoever takes over has a different approach." Lord Edward Lister, who was Johnson"s chief of staff when he was Mayor of London, will become interim chief of staff pending a wide-ranging shake-up of the prime minister"s team. Cain will be replaced by James Slack, who is currently the prime minister"s official spokesman. — Agencies