Good morning, this is Helen Sullivan bringing you the main stories and must-reads on Tuesday 2 September.

Top stories

Boris Johnson has publicly threatened to ignore the UK parliament if it mandates an extension to Brexit, saying there were “no circumstances” under which departure would not happen on 31 October. The prime minister said he would call a snap general election next month if the Commons pushes ahead with a bill tabled by a cross-party group of backbenchers seeking to block no deal. Johnson said publicly in a televised address he did not want an election. But No 10 briefings openly threatened one on 14 October if Tory rebels did not back down. But at least 17 Tory MPs said they had not been deterred from voting to stop a no-deal Brexit, as the EU considers whether to declare no-deal a “major natural disaster”.

Terrifying video footage is emerging from the Bahamas, where more than 13,000 houses have been destroyed or severely damaged by Hurricane Dorian. A full picture of the devastation has yet to become clear, with communications disrupted and emergency numbers down, as the intense storm barely moved on Monday from its position over the northern Bahamas. Meanwhile millions in the coastal US have been warned to “get out now” as the most powerful Atlantic cyclone of modern times set its sights on the US mainland. Follow our live blog for updates.

The Australian Medical Association has formally declared climate change a health emergency, pointing to “clear scientific evidence indicating severe impacts for our patients and communities now and into the future”. The AMA’s landmark shift, delivered by a motion of the body’s federal council, brings the organisation into line with positions taken by the American Medical Association, the British Medical Association and Doctors for the Environment Australia. Meanwhile the tech company Atlassian has joined an alliance of companies urging business to support this month’s climate strikes.

World

Facebook Twitter Pinterest Carrie Lam says she would quit as Hong Kong CEO if she had a choice. Photograph: Ann Wang/Reuters

A leaked audio recording has emerged in which Hong Kong’s leader, Carrie Lam, can be heard saying she would quit if she had “a choice”, suggesting she was being prevented from doing so by authorities in Beijing.

Up to 34 people are feared dead off the coast of southern California after a diving boat caught fire in the early hours of Monday morning, with crew members jumping off the deck to escape, while passengers were asleep below decks.

Iran and France have moved closer in their views on the future of Tehran’s nuclear deal with the west after talks between the countries’ presidents, the Iranian government has said.

A Chinese app, Zao, that uses deepfake technology to allow users to convincingly swap their faces with film or TV characters has triggered a privacy row after rapidly become one of the country’s most downloaded apps.



Greta Thunberg has spoken about her Asperger’s syndrome diagnosis after she was criticised over the condition, saying it makes her a “different” but that she considers it a “superpower”.

Opinion and analysis

Facebook Twitter Pinterest Everton de Freitas, 18, Laisa Conceição, 17, and Eliseu Assunção, 18, in Salvador’s Pau da Lima favela. Photograph: Dom Phillips/The Guardian



Volunteers in Salvador’s favelas are collecting data on deadly infections and inequality to help campaign for better sanitation. “Wearing crisp, white T-shirts and carrying tablets, the students fan out through Marechal Rondon, a bustling favela spread over hillsides and a valley in Brazil’s north-eastern city of Salvador,” writes Dom Phillips. “As they walk, they map blocked drains and piles of rubbish on their tablets. These are the “infection points” that attract the rats and mosquitoes which, in turn, spread diseases like leptospirosis and the Zika virus, both prevalent here.”

The data leading to the release of Australia’s GDP figures on Wednesday indicate that the economy will remain weak. The government doesn’t seem to expect decent figures as the prime minister suggests ignoring the figures and waiting for the ones to come out in three months’ time, writes Greg Jericho: “That’s all well and good, except of course the government was in charge for the five-and-a-half years before the June quarter, so it’s a bit rich to say ignore that and wait for September when our plan starts working.”

Sport

The US’s Naomi Osaka is out of the US Open, beaten 7-5, 6-4 by Switzerland’s Belinda Bencic. Donna Vekic fought back to defeat Julia Georges in three sets.

Steve Smith has been told to expect a brutal return to the Test arena on Wednesday, when Australia take on England in the fourth Test at Old Trafford, with Jofra Archer said to be eager for round two of their Ashes duel.

Thinking time: How a new pill could spell the end of ageing

Facebook Twitter Pinterest A simple treatment to stave off the health problems of old age could be available in five to 12 years. Illustration: Guardian Design/ Getty Images

The science of extending life is a subject of morbid fascination, conjuring the image of old billionaires being cryogenically frozen. But imagine if, instead of a pill you could take to live forever, there was a pill that could push back the ageing process – a medicine that could stave off the fragility, osteoarthritis, memory loss, macular degeneration and cancers that plague old age.

It could happen, with the science of senolytics: an emerging – and highly anticipated – area of anti-ageing medicine. Many of the world’s top gerontologists have already demonstrated the possibilities in animals and are now beginning human clinical trials, with promising results. If the studies continue to be as successful as hoped, those who are currently middle-aged could become the first generation of oldies who are youthful for longer – with a little medical help.

Media roundup

The Age and the Sydney Morning Herald declare that the economy is “on the brink of a 20-year low”, but the Herald splashes on the latest from the Independent Commission Against Corruption, reporting that the former state MP Ernest Wong rejected a claim that he disguised a $100,000 donation. The Australian reports that some of Australia’s biggest ­companies have failed to change auditors for decades “raising concerns about a heightened risk of corporate disasters under a practice that has been outlawed in Britain and Europe”.

Coming up

The former US secretary of state John Kerry will deliver the keynote address to the Global Table future of food conference in Melbourne.

Former Labor MP Ernest Wong will continue to give evidence before the NSW anti-corruption inquiry into a potentially unlawful donations scheme.

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