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Russian spy row: Putin facing deadline to explain

The clock is ticking, but will Russian President Vladimir Putin respond? Prime Minister Theresa May has said it's "highly likely" that Moscow was responsible for the use of the Russian-developed nerve agent Novichok in an attack on one of its former spies in the city of Salisbury. So she's set Mr Putin a midnight deadline to explain what happened.

Sergei Skripal and his daughter Yulia remain in a critical but stable condition in hospital, while Det Sgt Nick Bailey, who attended the scene, is also seriously ill. Those nearby when the attack happened have been urged to wash their clothes and belongings.

France and the US have offered the UK their support, but Russia says the claims against it are "unfounded". Home Secretary Amber Rudd will chair a meeting of the government's emergencies committee Cobra later. Here's what we know so far about the case. And we ask how the UK could retaliate.

Meanwhile, ahead of Russia's presidential election, what does the world think of Mr Putin?

Hammond to deliver spring statement

Chancellor Philip Hammond is expected to announce the UK economy is in better shape than expected when he gives his spring statement later. In a break with recent tradition, he won't be announcing any tax or spending measures - leaving those for the Budget in the autumn. Mr Hammond's expected to say he's resisting calls from Labour and some fellow Conservative MPs to use extra money from taxes to ease pressures on public spending, sticking to the argument that the national debt is still too high.

But BBC political editor Laura Kuenssberg has learned that cabinet ministers have been discussing ways of getting more money to the NHS in England, including possible tax rises or even a specific tax for health. The statement gets under way at 12:30 GMT.

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Deal offered on university pensions

A strike over threatened pensions has disrupted more than 60 universities for the last three weeks, but union leaders will meet later to discuss a proposed deal. Vice-chancellors are offering a new, independent re-evaluation of the pension deficit and temporary arrangements to tackle the funding gap. If no deal is reached, it's possible there could be more strikes in April and May.

The story of sickle-cell disease, starting 7,300 years ago

Once upon a time in what is now the Sahara desert, a child was born with heightened immunity to malaria - important because at the time this part of Africa was wet and rainy and covered with forest. It was a great habitat for mosquitoes. This child of 7,300 years ago had a better chance against an illness that was a major killer, then as now. Or maybe there were a few different children. People with this heightened immunity lived longer and had more children, and those children spread out further, all bolstered with extra defences against malaria. Their descendants still have those extra defences today, more than 250 generations later. But here's where the bad consequences come in.

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What the papers say

"From Russia... with hate" is Metro's headline, while the Sun tells Russia's President Putin "We've Vlad enough." The newspapers are dominated by the prime minister's statement that Moscow is likely to be behind the Salisbury nerve agent attack, with the Daily Mail questioning whether the England team can now attend the summer's World Cup in Russia. And the Daily Telegraph calls Theresa May's demand for an explanation by midnight "an ultimatum". In other news, there are tributes to comedian Ken Dodd, who's died aged 90, while the tabloids show great interest in the plight of Sky football pundit Jamie Caragher, after he spat at a car, hitting a 14-year-old girl.

Daily digest

Nepal air crash Survivors describe chaos as plane downed at Kathmandu's Tribhuvan airport

Train delays Passenger sues Greater Anglia over "woeful" service

North Korea Singapore firms have violated sanctions by supplying luxury goods, says UN report

Game of chicken Rival accuses Nando's of "bullying" as restaurant giant asks it to rebrand

If you see one thing today

Image copyright Cunard

Stars of the silver screen all at sea

If you listen to one thing today

When Ken Dodd did Desert Island Discs

If you read one thing today

We gave seven smart speakers an IQ test

Lookahead

13:30 Jump racing's most prestigious meeting, the Cheltenham Festival, starts. It runs until Friday, which is Gold Cup day.

18:30 US President Donald Trump visits San Diego, California, to inspect eight prototypes of his planned border wall with Mexico.

On this day

1996 Lone gunman Thomas Hamilton goes on a shooting spree at a school in Dunblane, near Stirling, killing 16 children and their teacher.

From elsewhere

His American dream died. His town got over it (Washington Post)

For decades, our coverage was racist (National Geographic)

The Victorian chemist who made it possible for Prince to wear purple (Independent)

World's first Casanova museum to open (Daily Telegraph)

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