First Thing: Trump in Canada tariff backdown after ‘substantial progress’ made on trade deal

Good morning. Donald Trump has paused his threatened punitive tariff on Canada just hours before it was due to come into effect. After Trump’s announcement, the Canadian prime minister, Mark Carney, said “substantial progress” had been made towards a trade deal, but more work was needed.

Tuesday’s ۱۱th-hour backdown comes after a contentious year for the two countries, with the longstanding alliance strained by tit-for-tat tariffs and online broadsides in which Trump has mused about wanting to turn Canada into a US state.

In February ۲۰۲۵, the White House hit Canada with a ۲۵% tariff, citing what it regarded as inadequate progress in curbing cross-border illegal immigration and drug trafficking. In retaliation, Canada announced a reciprocal levy, calling the US’s actions “unwarranted and unreasonable”.

• How much trade do the two countries do? Historically, Canada and the US have been strong trading partners. In ۲۰۲۴, trade between the countries was estimated to be roughly $۹۰۹bn, according to the office of the US trade representative.

Democratic socialist Angie Nixon clinches surprise primary win in Florida US Senate race

In an upset for the Democratic establishment, the progressive Angie Nixon won the party’s US Senate primary in Florida, beating the former army intelligence officer Alexander Vindman. Nixon, a state representative and member of the Democratic Socialists of America, had significantly less funding going into the primary. Vindman served on the national security council in Trump’s first term and became a well-known whistleblower and witness in the president’s first impeachment.

• What else happened in Florida’s elections? Byron Donalds, a congressman backed by Trump, won the Republican nomination for governor in the race to succeed Ron DeSantis. Donalds trounced three reasonably prominent Republican rivals, including Jay Collins, DeSantis’s handpicked lieutenant governor. If he wins the November election, as he is expected to do in the conservative stronghold, Donalds would become the first Black governor in any southern US state.

OpenAI announces slowing pace of development after hack by rogue agent

OpenAI said it had slowed down the ⁠pace of ⁠its ​AI development while it overhauled its ⁠research and training systems. The company’s researchers were ⁠caught unaware last month ​when an ‌AI agent ‌under testing hacked another AI ‌firm, Hugging Face.

The AI research lab behind ChatGPT said its new measures included pausing its model testing for two ‌weeks and investing more in adding other systems to monitor the activities of AI agents in testing. Some of ⁠the company’s largest planned training runs ​remained ​on hold, ​it said.

Pentagon threatens to cut federal funding to ۳۰ universities over foreign academic partnerships

Thirty US universities could lose federal funding unless they review and cut foreign academic partnerships the Pentagon considers a national security risk within the next two weeks, under a Pentagon directive aimed largely at ties to Chinese institutions.

Harvard, the Massachusetts Institute of Technology, Johns Hopkins, Georgetown and Cornell are among the institutions ordered to conduct and report the reviews – and end partnerships deemed problematic – by ۳۱ August, according to a US official who provided the full list to the Guardian.

“The ‘Department of War’ has zero tolerance for academic partnerships that compromise our national security,” Emil Michael, the Pentagon’s chief technology officer, said in a news release.

In other news …

• Harvard University has agreed to pay a $۵۳m settlement to resolve civil lawsuits stemming from the illegal theft and sale of human remains that had been donated to its medical school for scientific research.

• A man accused of attacking two people at New York City synagogue on Friday has been charged with federal hate crimes.

• The ZZ Top drummer Frank Beard has died at the age of ۷۷.

• The National Trust for Historic Preservation has urged the US supreme court to suspend Trump’s $۴۰۰m White House ballroom project while it considers whether the work can continue.

• Engineers from Elon Musk’s SpaceX are on their way to a remote Australian island to retrieve part of a Starship that dived into the Indian Ocean.

Stat of the day: Shares in humanoid robot firm Unitree surge ۶۰۰% on Chinese stock market debut

Unitree’s robots have gained global fame via videos of them performing martial arts and as dancers for pop stars. The company, which was founded in ۲۰۱۶, shipped more than ۵,۵۰۰ humanoid robots last year.

Well Actually: Iceberg, romaine, kale – which salad greens are healthiest?

“Eat your greens!” was a constant refrain in my childhood, and a mantra I found myself repeating as a parent. Adrienne Matei has everything you need to know about why it is important and how to get the best bang for your buck in terms of nutrition.

Don’t miss this: Brain-breaking sex, bad boys in leather and queer glory – why TV vampires are so intoxicating

My vampires of choice will always be Spike and Angel. Here Kayleigh Dray explores why everybody loves a bad boy – or girl – blood-sucker on TV. Why we are so hooked? Because, Kayleigh says, vampires embody absolute freedom, power, immortality, beauty and often forbidden love.

… or this: Sonic the Hedgehog at ۳۵ – from ۲D to ۳D to a billion-dollar film franchise

I probably spent more time at college playing Sonic than I did studying. Keith Stuart looks back at the history of the world’s fastest blue hedgehog, while thankfully ignoring the unnervingly human teeth that he briefly had in that dreadful initial movie trailer.

Climate check: Carbon pollution has fuelled ‘massive expansion’ of marine heatwaves in Europe, study finds

The hottest fortnights of this year would have been “virtually impossible” in a preindustrial climate in three of the four sea regions studied, according to analysis by World Weather Attribution, while in the Celtic region, which covers much of the water around the British Isles, heat hit levels that used to strike just once a century.

Last Thing: Tourists on pastry quest overrun scenic spot in Italian mountains

Hundreds of people have overwhelmed a mountain hut in the Italian Dolomites, not for the panoramic views but in search of a creamy pastry, reigniting the debate about social-media-driven tourism.

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