Sunak won the two previous televised debates, according to snap polls, and the second one featured a no-holds-barred clash with Truss.
A surge in debt costs - pushed up by soaring inflation to twice their previous monthly peak - added to Britain's budget deficit in June, which was its highest since April 2021, data showed on Thursday.
Differences over how to revive Britain's slow-growth, high-inflation economy could hardly be starker within the ruling Conservative Party as the two remaining contenders to become its new leader, and thereby prime minister, clash over tax.
The record-breaking heat has turned Britain into a microwave oven, disrupting the daily lives of the citizens.
It was wrong to hold a secret hearing which decided that the will of Prince Philip, Queen Elizabeth's late husband, should be sealed and kept private for 90 years, lawyers for a newspaper told the Court of Appeal in London on Wednesday.
The extreme heat caused huge transport disruption and sparked the same kind of wildfires seen in Europe in recent years.
If it's not the pictures of her standing atop a tank in a nod to Conservative leader Margaret Thatcher, it's the meme-defining moment when she vented her anger over cheese imports into Britain that made Liz Truss something of a household name.
Rishi Sunak will claim credit for steering Britain's economy through the COVID-19 crash but must overcome accusations that he is too rich and too willing to raise taxes to win the race to be the next prime minister.
Former finance minister Rishi Sunak and foreign secretary Liz Truss will battle it out to become Britain's next prime minister after they won the final lawmaker vote, setting up the last stage of the contest to replace Boris Johnson.
At least 13 people have died in Britain while swimming during a spell of record-breaking hot weather that sparked wildfires, damaged train tracks and triggered warnings that efforts to tackle climate change needed to be stepped up.
Surging petrol and food prices last month pushed British inflation to its highest rate in 40 years, according to official figures that bolstered the chances of a rare half percentage-point Bank of England interest rate hike next month.
An anonymous UK ticket-holder has won a record jackpot of £195m in the EuroMillions lottery. It is being termed the biggest National Lottery win of all time.
In a horrific incident reported from Brynhyfryd, Rhymney, seven dogs were burnt alive in an arson attack on their kennel.
In parliament, the strict dress code was even relaxed, with male MPs allowed to take off their jackets.
British employers agreed average pay rises of 4% with their staff in the three months to the end of June, the joint-highest since 1992 but falling further behind inflation, industry data showed on Wednesday.
Almost half of Britons are changing what they buy to feed their families as they try to navigate a worsening cost-of-living crisis, according to survey data published on Wednesday.
British officials repeatedly warned the government not to pursue its plan to send migrants to Rwanda and the country was initially excluded from the shortlist of partner countries because of human rights concerns, London's High Court was told on Tuesday.
Britain's former finance minister Rishi Sunak again topped the latest vote by Conservative MPs to choose a new prime minister, as another candidate was eliminated to leave three contenders in the race.
British financial regulators will have to promote the global competitiveness of the country's financial sector, though a plan for more government oversight of their work has been put on hold for now, finance minister Nadhim Zahawi said on Tuesday.
A 13-year-old boy was found dead after "getting into difficulty," while swimming in a West Yorkshire canal, according to police.
Britain was bracing for temperatures to hit 40C for the first time on Tuesday after it recorded its warmest night on record, forcing train services to stop, some schools to close and zoos to feed animals with large ice lollies.
A 43-year-old woman was mauled to death by her own dog at her house in West Melton, near Rotherham, South Yorkshire on Friday.
Sales of electric fans, hoses, air conditioning units and sprinklers are soaring as Britons swelter amid record temperatures, retailers said.
Britain was on course for its hottest day on record on Monday with temperatures forecast to hit 40C for the first time, forcing train companies to cancel services, schools to close early and ministers to urge the public to stay at home.
More than 28,500 people -- most of them young men -- arrived in 2021
Britain's government must focus on sound public finances and avoid further fuelling inflation by pumping up demand, new finance minister Nadhim Zahawi is due to say in his first major speech on Tuesday.
MPs will keep voting until only two candidates remain, the winner then being decided by the party members.
A top Bank of England official pushed back on Monday at suggestions from a leading candidate to become Britain's next prime minister that the government should set a "clear direction of travel" for monetary policy.
Global aviation's Farnborough airshow opens Monday amid a sweltering heatwave, with the sector aided by a modest recovery in air traffic and with Ukraine boosting defence budgets.
Britain, France brace for temperature records as Europe fires rage