Russia-Ukraine war LIVE: Vladimir Putin 'to introduce martial law' and Briton Ian Umney saves family

Russian forces seized a Ukrainian seaport and besieged another today as they tried to cut off the country from its coastline while Vladimir Putin's invasion continues.

The Russian military said it had control of Kherson, a Black Sea port of 280,000 people, making it the first major city to fall since the invasion began a week ago.

Elsewhere, the Russians pressed their offensive on multiple fronts, but a column of tanks appeared to have been stalled for days outside Kyiv. And the European Union said it had seen signs online that Russia could introduce martial law in the country. 

Ukraine said Russia's forces have so far suffered 9,000 casualties in the fighting. Russia said yesterday that nearly 500 troops have been killed and 1,600 wounded.

And Russian Foreign Minister Sergei Lavrov today warned that World War Three would be 'nuclear', while the Ukrainian city of Odessa was braced for an assault.

But Moscow's isolation deepened as most of the world demanded it withdraw from Ukraine and the UK said it was 'fast-forwarding sanctions' against oligarchs. 

Ukraine said more than 2,000 civilians have died, while the United Nations refugee agency revealed that one million people have fled the country since the invasion.

A second round of 'peace talks' aimed at ending the fighting in eastern Europe was expected to take place today, but there were little hopes of a breakthrough.

And an International Criminal Court war crimes investigation has begun after Boris Johnson accused Mr Putin of committing atrocities by bombarding cities.

Meanwhile Ikea became the latest firm to halt operations in Russia as it temporarily shut all stores and factories in the country in a move impacting 15,000 workers. 

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