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Israel says it killed Iran’s national security chief, Ali Larijani, in overnight strikes. If the claim is confirmed, it would make Larijani the most senior Iranian figure to die in the war since the supreme leader Ali Khamenei was killed on its first day.

Israel’s defense minister, Israel Katz, said a separate strike killed the Basij paramilitary force commander, Gholamreza Soleimani, along with other senior Basij figures. Iran has not yet commented on either claim.

On Monday European leaders rejected Donald Trump’s calls to send warships to the strait of Hormuz, despite the president’s threats about Nato’s future if members refused to help the US reopen the channel.

European politicians have backed diplomatic efforts to reopen the strait, through which about a fifth of the world’s oil and gas flowed until Iran blocked it. Germany, Italy and France said they did not plan to send ships, while the UK said it would not be “drawn into the wider war”.

Hundred of thousands of displaced Lebanese people fear that Israel is preparing for a prolonged occupation after it announced a ground campaign in new areas of southern Lebanon on Monday. Katz said displaced Lebanese forced from their homes would not be allowed to return until the safety of Israelis near the border was guaranteed, drawing comparisons with Gaza.

• How significant could Larijani’s death be? Very. If confirmed, it would remove a pivotal figure at the center of the regime’s political and security establishment at a time of acute crisis.

• What’s happening to oil prices? Oil and gas prices have risen again after Iran successfully attacked production facilities for the first time since the start of the war. Brent crude reached $103.2 a barrel on Tuesday.

• Read our live coverage here.

Federal judge blocks RFK Jr’s overhaul of vaccine recommendations

A federal judge has blocked Robert F Kennedy Jr’s unprecedented overhaul of vaccine recommendations and ruled that his appointment of a controversial panel of vaccine advisers likely violated federal law, staying all votes taken by the committee.

Judge Brian E Murphy ruled on a lawsuit brought by the American Academy of Pediatrics (AAP) against the US Department of Health and Human Services (HHS). Richard Hughes IV, one of the lawyers representing the AAP, said: “This is a major victory.” The federal government may appeal.

• What law did Kennedy break? He likely violated the Federal Advisory Committee Act when he fired all 17 members of the advisory committee on immunization practices and replaced them with his own hand-picked advisers, the judge found.

Trump predicts US will have ‘honor of taking Cuba’ amid power blackout

Donald Trump has said he expects to have “the honor of taking Cuba” after a US oil blockade caused the electricity grid to collapse, plunging the country’s 10 million people into darkness.

He claimed on Monday that he could do “anything I want” with Cuba amid US negotiations with Havana over the country’s future. “You know, all my life I’ve been hearing about the United States and Cuba. When will the United States do it?” Trump told reporters on Monday. “I do believe I’ll be … having the honor of taking Cuba.”

• What do we know about US ambitions for regime change in Cuba? The New York Times reported on Monday that US officials told Cuba to remove its president, Miguel Díaz-Canel, from power during recent talks, citing four unnamed sources familiar with the discussions.

In other news …

• Afghan officials blamed the Pakistani military for a strike on a hospital in Kabul on Monday that they said killed 400 people, though Islamabad dismissed allegations it had hit a civilian target.

• Voters in Illinois head to the polls on Tuesday to choose their next senator and five congressional district candidates in the state’s primary elections.

• Countries in Africa are particularly vulnerable to supply chain disruptions caused by the US-Israel war on Iran, experts have said.

• Thousands of flights have been canceled as a powerful winter storm hit the eastern US, with New York, Chicago and Atlanta among the cities affected.

Stat of the day: Oakland homicides down 48% from Covid peak

Last year, Oakland recorded its lowest number of violent deaths in 25 years. The Bay Area city ended 2025 with 67 people killed, according to data from the Oakland police department, half of its 2021 high of 134. From investments in historically neglected neighborhoods to improved policing technology, Abené Clayton looks at the factors driving the decline in violence.

Culture pick: Inside The Pitt: the stunning medical drama from the team behind ER

Developed by the team behind the 90s hospital hit ER, The Pitt follows hospital workers at a cash-strapped emergency room in Pittsburgh as they deal with everything from gunshot wounds and fentanyl overdoses to burnout. The Guardian goes behind the scenes of the show, which explores a patchwork of American social ills with a rollercoaster rhythm, to understand what makes it work.

Don’t miss this: How Elon Musk tried to gamify government

When Elon Musk joined the government as the de facto head of the “department of government efficiency”, he did so with the mentality that the US government was just a database to be optimized. “Over time, Musk had become convinced that the real bugs in the code were people,” write Ben Tarnoff and Quinn Slobodian in this long read on the billionaire’s slash-and-burn approach to government deregulation.

Climate check: Revealed: the world’s worst mega-leaks of methane driving global heating

There were dozens of massive methane leaks from oil and gas facilities in 2025, analysis of satellite data has revealed, with each mega-leak having the same global heating impact as a coal-fired power station. Although they have a colossal heating impact, the leaks could be easy to fix and researchers say it is “maddening” that action is not being taken.

Last Thing: 19 modern etiquette mistakes – and how to avoid them

Social media has made connection easier than ever – but it is also a minefield of potential faux pas. From checking your smartwatch notifications while you’re chatting with someone to sharing pictures of other people’s children online without permission, here are 19 common etiquette mistakes in the modern age.

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