At 11: 26pm on May 11, 2016 — at the height of the EU referendum campaign — political journalists who were still awake received an email from the official Vote Leave team.

Attributed to a “senior Vote Leave source”, it threatened ITV with “consequences for its future” after the channel chose Nigel Farage to represent Brexiteers during its televised debate, rather than Boris Johnson or Michael Gove.

Vote Leave chief Dominic Cummings had seen this as a politically biased decision by ITV to ignore the official Leave campaign and deliberately associate Brexit with the more divisive Farage. His email effectively put ITV on notice that if Cummings ever got into government, he would be seeking revenge.

The furious late night diatribe ranted that “ITV have effectively become part of the In campaign”, claiming: “ITV is led by people like Robert Peston, who campaigned for Britain to join the euro”. Peston described the email as a “mad slur”.

In the years since, former Vote Leave officials close to Cummings — several of whom are now in Johnson’s government and worked on the Conservative election campaign — have half-jokingly referenced the row to describe their battles with the media or other opponents. Raise an issue or person of contention with a Vote Leaver and they will often smile and reply simply: “Consequences.”

Now in Downing Street, “senior Number 10 sources” are making good on that threat. Since Johnson’s election win last month, his top team has launched a war on the media on several fronts that includes existential reforms for the BBC and Channel 4, day-to-day changes to the government’s relationship with broadcasters, and a controversial shake-up of the Lobby system of Westminster correspondents.

Those responsible for the changes — Cummings and the Downing Street director of communications Lee Cain — flatly reject the suggestion that they are at war with the media. They argue they are simply implementing long-needed reforms to the licence fee which are popular with the public, modernising archaic conventions in an out-of-touch Lobby, and shifting the government’s media strategy away from the entitled demands of the traditional media, and towards the public.

Look at them individually and each skirmish between Number 10 and the media can be viewed as an argument where both sides have a point. But taken together, few in either the media or outside of Downing Street dispute that there is an orchestrated campaign from Johnson’s aides to divide and disrupt their journalist critics — in tactics described as “Trumpian” across the board last week.

Some in Johnson’s administration are strongly opposed to this strategy, fearing that Number 10’s uncompromising behaviour is creating unnecessary enemies and starting fights it will ultimately never win. BuzzFeed News can reveal a deep divide has opened up at the top of government over whether Johnson should order his aides to make peace.

The big picture story is that Johnson ultimately appears to back what his senior team see as a culture war against elements of the British media establishment that they perceive have not only opposed their politics for the last three-and-a-half years, but for decades.

Johnson is determined to exert a heavy influence over the decision of who will be the next BBC director general, preventing the appointment of a liberal-centrist and potentially endorsing a controversial Conservative-leaning political candidate. “The BBC has had a long list of political director generals, chairmen, and senior executives. Why should we be any different?” a source said.

Number 10 is entirely serious in its plans to decriminalise non-payment of the licence fee and review Channel 4’s public service broadcasting obligations, as BuzzFeed News revealed during the election.

Senior Tories told BuzzFeed News that they object to licence fee payers’ money being spent on what they see as “woke” BBC comedy programmes, dramas exhibiting liberal biases, and projects such as the online BBC Three. One said Channel 4 News would no longer be allowed to “make a mockery of Ofcom impartiality rules night after night”. Johnson has not forgotten that Channel 4 News’ editor Ben de Pear once liked a tweet calling him a “cunt”.

This is a government that privately cheered Laurence Fox’s incendiary Question Time appearance in which the actor claimed “to call me a white privileged male is to be racist”. Since then, two senior ministers have praised Fox’s comments to BuzzFeed News. “The public are sick of having this crap stuffed down their throats by the media for years. We don’t have to go along with it any more,” one said.

But declaring open warfare on the media has had early “consequences” for Johnson too. The most glaring example came on Brexit night, when Downing Street informed broadcasters that they would not be permitted to film a typical “pool” clip of the prime minister’s address to the nation — where one broadcaster sends in their cameras and then shares the footage with other outlets. Instead, the government would be filming the video and expected the broadcasters to air it on the 10 O’Clock News.

Johnson spent hours crafting his speech for his big moment and pre-recording it for the Number 10 cameras. But, outraged at the break in convention and the attempt by the government to control the images, BBC and ITV called Downing Street’s bluff and refused to run his video. Senior Tories were apoplectic at that decision, but accepted that their own attempt to bounce the broadcasters into doing what they wanted had badly backfired.

Number 10 is happier with its boycott of the BBC Radio 4’s flagship Today programme. Furious once again at perceived bias, the government banned its ministers from appearing, and has received private feedback from some political journalists that they have stopped listening because it no longer breaks news as a result. The BBC was keen to point out this week that the Today audience had increased during the boycott. “The Today stuff is about the Lobby, not the general public,” a government source said.

But other ministers are less keen. Justice secretary Robert Buckland — who has long been at odds with Downing Street over its hardline Brexit strategy before the election — signalled his doubts, telling the BBC: “I love the Today programme. Radio 4 has been my programme of choice for about 30 years”. There was particular unease that, the morning after the Streatham terror attack, a government minister was not put forward for a full broadcast round.

Also boycotted by the government is ITV’s Good Morning Britain, after its host Piers Morgan launched a series of personal attacks on Cain and the Downing Street press secretary Rob Oxley. Johnson and his ministers have instead been put on BBC Breakfast, which has around double the viewers.

Tory sources have said they want to reach the public more via new media and social media, rather than traditional news outlets, ironically echoing Labour leader Jeremy Corbyn in his own battles with the press. Johnson has taken part in a regular “People’s PMQs” session on Facebook, where he reads out mostly softball questions from punters. The format has not received universal acclaim. “It is fucking shit,” one Conservative MP told BuzzFeed News.

If you’ve been on Twitter recently you will have struggled to miss the ongoing brawl between Number 10 and Westminster’s political journalists, known collectively as the Lobby. First, the Labour-supporting Daily Mirror newspaper was barred from the Tories’ election battle bus. Then Number 10 decided to move their decades-old Lobby briefings from Parliament to Downing Street — to the fury of journalists who feared they would be on “away territory” and that government spinners would be able to control access. The Society of Editors signed a letter to Johnson urging him to reconsider the changes, with Downing Street still refusing to engage.

Last week, that smouldering row fully ignited as the Lobby staged a walkout in protest at Cain inviting some senior reporters to what Number 10 described as an “inner Lobby” briefing with the prime minister’s Brexit special adviser David Frost, but excluding others. Around 10 journalists were on the list, with five or six from other titles asked to stand on the other side of the room in Downing Street and barred from entering the briefing. All the reporters left when Cain refused to let the uninvited ones in.

It is not out of the ordinary for Number 10 to hold off-the-record briefings for selected journalists, something that happened routinely under Theresa May’s regime. In July 2018, May’s senior aides Gavin Barwell and Robbie Gibb invited reporters and pundits from Tory-sympathising outlets including the Spectator, Conservative Home, Guido Fawkes and the Mail on Sunday to attempt to convince them to support her Chequers plan. The meeting did not go to plan, with one prominent journalist lambasting May’s Brexit proposals then walking out.

A political editor who was invited to the Frost briefing confirmed to BuzzFeed News the existence of an “inner Lobby” which has met occasionally under Johnson’s premiership. Its membership included the political editors of most national newspapers, as well as the BBC’s Laura Kuenssberg and ITV’s Peston. The problem arose when the political editors of the Mirror, the i, Huffington Post and PoliticsHome found out that they had not been invited, and kicked off.

BuzzFeed News also understands that one government department temporarily removed the Mirror from its press release list over what it claimed was inaccurate coverage.

Some in the Lobby accept that a few of its senior members have been known to be precious about these things. But one Lobby journalist accused Number 10 of “blatant divide and rule tactics” seeking to turn reporters from rival publications against each other, rather than spend their time scrutinising the government. If that was the plan then some reporters indeed fell for it, although “inner Lobby” journalists have now agreed not to attend briefings from which other colleagues have been excluded.

The ongoing dispute with the Lobby is concerning ministers, their media special advisers, and even senior civil servants — with cabinet secretary Mark Sedwill said to be worried about recent developments.

Departmental media aides — whose job it is to secure positive press coverage for cabinet ministers — told BuzzFeed News they were confused by Downing Street’s strategy. One noted they had been told not to accept lunches from journalists and speak to the Lobby, yet they see anonymous quotes from Number 10 in the newspapers every day.

Another media special adviser said their life had been “made impossible” by Cummings’ insistence that there can be no cabinet minister media visibility except if it has been cleared by Number 10 and put on the Downing Street grid — its weekly communications plan. “But the grid is weak,” they said.

Johnson appears to have given his authority to the overarching strategy his aides have adopted towards the media, especially in terms of the long-term future of the BBC and Channel 4. Whether he is as keen on the day-to-day skirmishes with individual outlets and journalists remains to be seen. “I am a journalist. I love journalism,” he told the Commons at prime minister’s questions on Wednesday.

A veteran former media special adviser said: “What it comes down to is, is this helping the PM or hurting him. He is certainly up for a fight on the major media issues affecting the country, but there comes a point where you have to ask if some of this is causing more harm than good.”