Secret tunnels, nuclear codes and a blizzard of left-wing policies: GLEN OWEN, DAN HODGES and ANNA MIKHAILOVA on Starmer’s first day in No.10

It’s not over until the fat lady sings, but if the polls are anything like the truth, it will take the political equivalent of an asteroid destroying the Earth to stop Sir Keir Starmer walking through the door of No 10 on Friday.

The well-oiled machinery of the British state has been spinning towards this potentially seismic moment for more than a year: Sue Gray, who spent years at the top of the civil service before moving to become Starmer’s chief of staff, has led the transition talks. – and laid out the grid for the first 100 days of a Labor government.

With the parliamentary recess approaching at the end of July, Starmer is expected to take swift action to cement his state vision for the country’s future. He will take, among other things, the repeal of the Rwandan migrant scheme, trade union laws based on the French model and the abolition of VAT on school fees for private schools as examples.

When he returns from his visit to Buckingham Palace to ask the King for permission to form a government, Starmer will make a short speech from Downing Street before being greeted at the door of No 10 by Cabinet Secretary Simon Case.

After being pushed through the door by staff, he is led to the cabinet room to meet his most senior officials. It was at this point in 2019 that Boris Johnson began to talk about what he had discussed with the Queen, until he was quickly reminded that a protocol of sovereign discretion applies.

Chillingly, Starmer, whose predecessor Jeremy Corbyn vowed never to use the nuclear deterrent, is then told by a senior naval commander to write four identical handwritten letters of last resort to the commanders of the Trident submarines.

Starmer’s first task will be to listen to a detailed personal security briefing – he is given the option of inviting his wife and two children along – on topics including a terrorist attack on No 10. A source said: ‘The new prime minister is literally being told they must leave immediately, without argument or discussion, via a network of secret tunnels that run beneath Whitehall.’

Chillingly, Starmer, whose predecessor Jeremy Corbyn promised never to use the nuclear deterrent, is then ordered by a senior naval commander to write four identical handwritten “letters of last resort” to the commanders of Trident submarines – orders that will be carried out if the government is wiped out by nuclear attack. An industrial-sized shredder will be brought in to destroy the existing letters from Rishi Sunak. David Cameron responded to this on his first day in office in 2010 by putting his hand to his forehead and exclaiming: “Oh my God, this is real!”

Starmer will also have to draw up a shortlist of top aides he would like to join in a nuclear bunker – a subject of jealous infighting in previous regimes.

The first calls from world leaders will now come in. A source said: ‘This is seen as very important. The first conversation sets the tone for the new diplomatic relationship.

“A lot of thought goes into what the first ‘ask’ to each world leader will be, what they will demand in return and what the response will be.”

While all this is going on, Starmer will also be introduced to the duty clerks, Garden Room Girls and the manager of the Prime Minister’s flat – he will live ‘above the shop’ with his family – who will soon be jointly managing his daily life on a minute-by-minute basis.

A government source said: “It quickly becomes clear to the new prime minister that these people will be running almost every aspect of his day-to-day affairs. Then they realise that they are not just taking on a new job, they are giving up their lives. It is very detailed.

‘They ask what time the prime minister wants to be woken up – do they want a phone call or a knock on the door, do they want breakfast in the apartment or something else on their desk? Do they want official documents to be picked up or would they rather work on them in the main building? That sort of thing.’

Starmer’s thoughts will then turn to appointing his Cabinet. While most of his senior frontbench members are expected to take up their positions straight away, there is still room for surprises: Shadow Foreign Secretary David Lammy will be particularly nervous after a whisper campaign against him sparked by his virtual absence from the campaign trail.

Gray has been in close contact with shadow cabinet ministers during the campaign to test their readiness for government, summoning many to face-to-face meetings at her office in Labour’s south London headquarters and quizzing them on their plans for the first 100 days. Central to the discussion was the measures to be included in Starmer’s July 17 throne speech, which would set out Starmer’s programme for legislation.

Gray started the process in September, shortly after taking up her post, when she instructed the shadow cabinet to be ‘fit’ for the first weeks in office.

An aide said of the former Whitehall mandarin: ‘She’s holding the pen. It’s been pretty seamless. She’s mainly told us to get on with our plans, but she’s also provided useful contacts to talk to about implementation and put forward her own ideas.’

Probably the most pressing problem is immigration. Labor has promised to scrap Sunak’s Rwanda migrant deportation plan ‘on day one’: with up to 60,000 migrants designated for deportation to Rwanda, they will by definition be given an effective ‘amnesty’ and placed into the asylum system.

Combined with an expected increase in small boat crossings, this could quickly end Starmer’s honeymoon. Shadow Home Secretary Yvette Cooper, who plans to start her new Border Security Command on day one, will usher in a ‘national security sprint’ to identify emerging threats to the UK.

Starmer will also have to draw up a shortlist of the most senior aides he would like to join him in a nuclear bunker, a subject of jealous infighting in previous regimes.

Her other plans include laws to tackle anti-social behaviour, improve preparedness for terrorist attacks and launch an inquiry into violence against women.

Shadow Chancellor of the Exchequer Rachel Reeves will first set a date for the next budget. She will also propose legislation in her speech from the throne to impose VAT on school fees for private schools from 2025.

Labour deputy leader Angela Rayner has spearheaded the party’s plans to introduce new workers’ rights through legislation, including ending zero-hours contracts and easing restrictions on union activity.

Wes Streeting, the presumptive health secretary, says he will reopen negotiations with the British Medical Association to try to end the doctors’ strikes.

He says his focus in the first 100 days will be on Labour’s promise to add 40,000 extra NHS appointments a week, provide direction to NHS trusts, set up surgical centres and force more NHS staff to work overtime at weekends and in the evenings.

Starmer will make his first foreign trip as prime minister just four days after taking office, attending a summit of the NATO alliance in Washington alongside Joe Biden and other world leaders. And on July 18, the prime minister will host key EU leaders for the European Political Community summit at Winston Churchill’s birthplace Blenheim Palace in Oxfordshire.

Churchill, writing about his own first day as Prime Minister in The Gathering Storm, said: “When I went to bed about three in the morning I was conscious of a deep sense of relief. . . At last I had the authority to give directions on the whole scene.”

If the polls are correct, Starmer’s own “power to give directions” will be almost completely unfettered.