After a bitter eight week long campaign, the Conservative Party will announce its new leader – who will become prime minister – on Monday.

This is how the next 72 hours are roughly due to play out.

At 12.30pm the winner of the leadership race will be revealed at an event at the Queen Elizabeth II Conference Centre in Westminster.

Liz Truss or Rishi Sunak will learn who has won – widely expected to be Truss – a few minutes before the result is made public.

The venue, a short walk from parliament and Downing Street, was also where Jeremy Corbyn was announced as Labour leader in 2015.

But the new Tory leader will not take over as prime minister immediately.

This will be Boris Johnson’s last day in office as PM. In the early morning, around 8.30am, he will deliver a farewell speech in Downing Street.

Johnson will then fly from London to Aberdeen and make his way to Balmoral to see the Queen and resign.

The Queen will then meet with the new Tory leader and appoint them prime minister.

Truss – or Sunak if he pulls off a spectacular upset – will then fly to London and deliver their first speech as PM outside No.10 at about 4pm.

It is then expected the that the new cabinet will be formed over the course of the next few hours.

Parliament returns from its long summer recess this week, which means the new PM will face Labour leader Keir Starmer at PMQs after about only 24-hours in the job.

Truss has promised to reveal within one week of taking office how she will deal with rising energy bills.

But the likely incoming PM has not said what form any help will take or given a precise date when she will unveil any plan.

Cutting VAT by 5% across the board would be a “regressive” move costing tens of billions of pounds, Rishi Sunak’s campaign team has warned.

According to The Sunday Times, Liz Truss is considering slashing VAT as part of an emergency package to help households cope with rising prices if she wins the Tory leadership race.

The newspaper said the 20% headline rate of VAT could be cut by up to 5%, saving the average household more than £1,300 per year.

But Sunak’s campaign said the move would “incredibly regressive” and cost more than £30bn.

Another option reportedly being weighed up by Truss is a cut to income tax, with proposals including increasing the level above which people start paying the levy.

Truss could also raise the tipping point for the higher rate of 40% and cut the basic rate below 20%.

Boris Johnson has said whoever succeeds him in No.10 would announce “another huge package of financial support” amid soaring energy bills.

The outgoing prime minister has refused to act again himself, deciding the country must wait until a new PM is in office to provide any new help.

The Treasury has said it is making the “necessary preparations” to ensure the next government has options to deliver extra help “as quickly as possible”.

Energy regulator Ofgem warned the government on Friday that it must act urgently to “match the scale of the crisis we have before us” as Britain faced the news that the average household’s yearly bill will rise from £1,971 to £3,549.

Sunak has already said he will provide additional support targeted at the most vulnerable.

Truss has promised “decisive action” to deliver “immediate support” if she wins the contest.

But she has so far been vague about what form this assistance might take apart from slashing green levies on energy bills and reversing the controversial National Insurance hike.

In an article for Mail+, Johnson acknowledged that the next few months will be difficult – “perhaps very tough” – as “eye-watering” energy bills take their toll, but he forecast the UK will emerge “stronger and more prosperous (on) the other side”.

He said “colossal sums of taxpayers’ money” have already been committed to assisting people with their bills.

But he added: “Next month – whoever takes over from me – the government will announce another huge package of financial support.”

Nadine Dorries is not running to be Tory leader. But her presence on the campaign trail has been arguably more attention-grabbing than either Liz Truss or Rishi Sunak.

The culture secretary and uber Boris Johnson loyalist, who is backing Truss in the race to succeed him, has deployed something of a scorched earth policy when it comes to taking revenge on Sunak.

Here are some of the highlights of her involvement in race so far.

In June, Tory MPs triggered a confidence vote in Johnson’s leadership of the party. The PM won, but the writing was on the wall as 41 per cent of the paerliamentary party voted to boot him from office.

Jeremy Hunt, who Johnson beat to the leadership in 2019, revealed he would vote against the PM in the first vote.

Dorries was so angered that in a series of tweets aimed at the former health secretary she publicly admitted the Conservative government had made “inadequate” preparations for the pandemic.

On July 6, cabinet ministers gathered in No.10 to tell Johnson the game was up and he had to resign. Nadhim Zahawi, Grant Shapps, Priti Patel and Brandon Lewis were among the delegation.

The prime minister learned what was waiting while giving evidence to a committee of senior MPs live on TV.

Dorries was also spotted heading into Downing Street. But she told reporters she was “definitely” not there to tell Johnson to quit. Instead she headed in to argue against the delegation’s demands.

3. Gets Zahawi’s job wrong

As cabinet ministers resigned from Johnson’s government, Dorries stood firm. But it took her three attempts to congratulate Nadhim Zahawi who had just been appointed as the new chancellor.

She tweeted support for Zahawi when he was appointed chancellor – but congratulated him on being made health secretary. Praising his ability to “achieve against the odds”, she noted: “He will deliver for health in the same way he delivered for vaccines and education.”

This message was quickly deleted and replaced. This time, she attached the same photo of Zahawi alongside two photos of Steve Barclay, who really had been appointed as health secretary. This message was then deleted too.

She eventually gave up uploading the photos herself, and instead retweeted the official No.10 account, praising both Barclay and Zahawi for their new appointments.

Dorries, who owns £6,000 diamond earrings, launched an attack on Sunak for having expensive shoes and suits compared to Truss’ £4.50 earrings.

Tory colleague Angela Richardson MP respond: “FFS Nadine! Muted.” The row led veterans minister Johnny Mercer, who attends cabinet, to despair that the contest was “embarrassing”.

Dorries later said she “may have gone over the top” with the attack on Sunak’s clothes.

She then shared a doctored image on Twitter showing Sunak stabbing Johnson in the back.

Writing in the Mail on Sunday, Dorries described Sunak as an “assassin” for helping to bring down Johnson, and a “dog in the manger” for not supporting the PM enough.

Business minister Greg Hands condemned Dorries’ actions as “distasteful” and “dangerous” in the wake of the killing of Southend West Tory MP Sir David Amess at a constituency surgery in Essex last October.

The contest still has five weeks to run.