Russia captured three Ukrainian naval vessels and 23 crew members sailing off the coast of Crimea, which was annexed by Russia in 2014. Russia opened fire, before its special forces stormed the vessels. Between three and six Ukrainians were injured. Ukraine said it was a Russian "act of aggression". Moscow said the ships had illegally entered its waters.

A number of Western countries condemned Russia's actions. In New York, the UN Security Council met to discuss the crisis - but failed to agree a Russian-proposed agenda amid sharp disagreements between Moscow and the West. In 2014, Ukraine's pro-Russian leader was overthrown, after large-scale protests against the government's decision to abandon plans to sign an association agreement with the EU. Russia then annexed Crimea, while Russia-backed separatists moved against the Ukrainian state in the east.

Donald Trump has suggested Theresa May's Brexit agreement could threaten a US-UK trade deal. The US president told reporters the withdrawal agreement "sounds like a great deal for the EU" and meant the UK might not be able to trade with the US. No 10 insisted it is "very clear" the UK would be able to sign trade deals with countries around the world. Downing Street added that Mrs May is ready to defend her deal in a TV debate with Labour leader Jeremy Corbyn.

It has been reported the debate could take place on 9 December - two days before the Parliamentary vote on Mrs May's deal. Speaking to reporters outside the White House, Mr Trump said: "Right now if you look at the deal, [the UK] may not be able to trade with us. And that wouldn't be a good thing. I don't think they meant that." Senior members of his administration maintain close contacts with prominent eurosceptics in the Conservative party.

But when the president says the agreement could jeopardise trade with the UK, it's hard to see what he means. During the transition period, business with the US would presumably carry on in exactly the same way as it does now.

The US space agency Nasa has landed a new robot on Mars after a dramatic seven-minute plunge to the surface of the Red Planet. The InSight probe aims to study the world's deep interior, and make it the only planet - apart from Earth - that has been examined in this way. Confirmation of touchdown came through on cue. It ended an anxious wait in which the robot radioed home a series of updates on its descent. Nasa's mission control at California's Jet Propulsion Laboratory (JPL) erupted into cheers when it became clear InSight was safe on the ground.

The agency's chief administrator, James Bridenstine, celebrated what he called "an amazing day". President Trump had rung to offer his congratulations, he told reporters. And the director of JPL, Mike Watkins, said the success should remind everyone that "to do science we have to be bold and we have to be explorers." InSight is now sitting on a vast, flat plain known as Elysium Planitia, close to the Red Planet's equator. The image was taken through the translucent lens cap of a camera positioned on the underside of the lander. The dust kicked up in the descent obscured much of the scene, but it was still possible to make out a small rock, one of the probe's feet and the sky on the horizon.

The British academic jailed for spying in UAE and sentenced to death in a recent court ruling thanked his "brave and strong" wife Daniela Tejada for helping secure his release. Matthew Hedges, 31, landed back at Heathrow Airport on Tuesday morning after receiving a pardon. He said: "I could not have done this without Daniela. I hear her face is everywhere. She is so brave and strong, seeing her and my family after this ordeal is the best thing that could have happened."

Mr Hedges, who was arrested at Dubai airport in May, said he was innocent and had been researching the country's security strategy as part of his PhD studies at Durham University.

However, a spokesman for the UAE government said Mr Hedges was "100% a secret service operative".