In what appears to mark a toughening in the US stance against Russia, Joe Biden last night declared Nato would respond "in kind" if Vladimir Putin resorted to using chemical weapons against Ukraine.
Asked if a Kremlin-orchestrated chemical attack would prompt a military response, the US president said: "It would trigger a response in kind."
His remarks came as he met Nato, G7 and European leaders at a series of emergency summits in Brussels. They discussed what to do if Mr Putin decided to unleash weapons of mass destruction.
As Europe Editor James Crisp in Brussels reports, Prime Minister Boris Johnson left open the possibility of a military response when pressed on the subject.
It came as Britain will double its troops in Eastern Europe after Nato leaders agreed to strengthen the alliance's eastern flank against Russian aggression.
But, speaking in a Facebook video early today, Ukrainian president Volodymyr Zelensky said Europe acted "a little too late" to stop Russia from invading Ukraine - claiming countries should have sanctioned Moscow and blocked the Nord Stream 2 gas pipeline earlier.
As photographs emerged of the full horror caused by the indiscriminate bombing of Mairupol, the senior Russian military figure in charge of the port city's destruction has been identified by Ukrainian officials as Colonel General Mikhail Mizintsev - a man dubbed the Butcher of Mariupol.
In an intercepted phone call, he can be heard apparently demanding a junior officer's ear be cut off for not wearing the correct uniform. Read more about his background and follow the latest updates on the ground in our live blog.
In other developments:
"Putin's chef" blamed Russophobia for losing his UK lawyers; Mr Johnson denied being "the most active anti-Russian leader"; and 40,000 people applied to open their homes to refugees. Sunak branded a 'fiscal illusionist' over tax cut claims
Rishi Sunak has been branded a "fiscal illusionist" as claims made in his Spring Statement began to unravel. The Institute for Fiscal Studies said nearly all workers would end up paying more tax on their earnings despite the Chancellor's claim to be delivering the "biggest net cut to personal taxes in over a quarter of a century". Amid a growing Tory backlash, the institute said the gains from Mr Sunak's plan to raise the thresholds for paying National Insurance and the 1p income tax cut in 2024 would be wiped out by his previous tax rises. It came as more than a million pension savers are facing a stealth tax raid as Mr Sunak capitalises on soaring inflation to boost his revenues. And banks have already rushed to pass on higher borrowing costs to homeowners.
Can anything be done to save the Commonwealth?
The Duke and Duchess of Cambridge's tour of the Caribbean coincided with a swelling wave of republicanism. Prince William did his best to fend off anti-colonialist attacks in his Jamaica speech, expressing his "profound sorrow" for slavery which "should never have happened". But was it too little too late? Is the monarchy rapidly becoming an anachronism? And will the Commonwealth soon be in the past? Harry Mount explores how much perception of the monarchy has changed.
PS: After the pandemic spoiled the Queen's plans to visit craftsmen in Staffordshire, see how they brought a "factory tour" to her own home.
Daily dose of Matt
In his latest cartoon for The Telegraph, Matt finds a joke in the P&O staffing debacle.
Also in the news: Today's other headlines
Novelist in race dispute | Sir Philip Pullman is embroiled in a cancel culture row and has resigned from a literary association over his support for an author accused of racist stereotyping. The 75-year-old writer of the His Dark Materials trilogy was facing calls to quit as president of the Society of Authors after defending Kate Clanchy, who was "cancelled" by her publishers after allegations that her prize-winning memoir portrayed some of her former pupils in a "racist" manner.
Elgin Marbles | 3D scans could support call for their return 'Why now?' | Anoosheh Ashoori accuses PM of opportunism Local crime scorecards | 'Police letting down too many victims' Met Office archive | Weather records shattered... 180 years ago 'Sad-go-lucky' | Believers in fate are unhappy, researchers find Dispatch: Tragic bedside tales from front-line hospital
On days of heavy fighting - or when humanitarian corridors open up - the large A&E hospital in western Kyiv receives dozens of wounded and dying. Like a warzone version of the medical drama ER, there are tales of survival and heroism - and episodes of utter tragedy. In his latest dispatch, with pictures by David Rose for The Telegraph, Colin Freeman hears chilling stories from patients' hospital bedsides.
Comment and analysis Fraser Nelson | Power struggle mired Tories in ideological confusion David Abulafia | Rustat verdict is a humiliation for woke activists Allison Pearson | NHS trans guidelines are straight from 1984 Judith Woods | Sunak the forecourt jester isn't fooling anyone Reader letters | Chancellor torpedoed credentials as a true Tory Editor's choice All at sea | The uncertain fate of superyacht industry kept afloat by Russian money The Apprentice: the Final, review | Lord Sugar did not seem to want either candidate Duchess's jewels | Why Kate has the Queen's most important hand-me-down bling Sport briefing: Italy to miss World Cup again
Italy missed out on the World Cup finals again after losing at home to North Macedonia in their play-off semi-final last night, as Aleksandar Trajkovski's last-gasp strike earned the visitors a win. In cricket, an unlikely last-wicket stand of 90 between Jack Leach and Saqib Mahmood kept England alive on day one of their series decider in the West Indies. And Emma Raducanu was a picture of dejection as she left the court in Miami after being beaten by gutsy Katerina Siniakova.
Business briefing: 'Woke brigade' critic heads Ofcom
A Conservative peer and critic of the BBC has been appointed as Ofcom chairman, Britain's media regulator. Lord Grade of Yarmouth - who as Michael Grade has held senior positions at the BBC, ITV and Channel 4 - was named as the Government's preferred choice for the ￡142,500-a-year role after the process to find a suitable candidate faced setbacks.
Tonight's dinner
Thick-cut bacon with brothy broad beans, peas and potatoes | Eleanor Steafel could not resist buying a great slab of English smoked bacon for this dish. Also try our Cookbook newsletter.
Travel: Romantic London hotels for a spring getaway
London is definitely up there as a contender for most romantic city, thanks to the strength and variety of its amorous abodes. In fact, it is often possible to get everything you need all under the one roof - ideal for a romantic weekend getaway. From cosy boltholes to flashy grande dames, these hideaways selected by Alison Taylor are perfect for two.
And finally... for this morning's downtime
'Stanley Spencer was eccentric, but he wasn't mad' | A family friend recalls sitting for the artist as a boy - and explains why Spencer wore pyjamas under his trousers at Sunday lunch. Richard Martineau reminisces with Chris Harvey.
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