Here is a summary of the situation on the ground, based on statements from the warring sides, Western defence and intelligence sources and international organisations.

The military situation:

- Russia says will continue "until set goals are achieved".

- Satellite images show 65-kilometre (40-mile) column of Russian trucks, armoured vehicles and artillery north of Kyiv.

- Citizens build barricades in city centre.

- Russia tells residents near Kyiv intelligence structure to evacuate.

- Ukraine says Russian strike targets Kyiv main TV tower and knocks out some state broadcasts.

- Russian troops and pro-Moscow rebels link up in a key region in eastern Ukraine, Moscow says.

- Ukraine says has taken out hundreds of Russian pieces of weaponry, including 29 aircraft, 29 helicopters and 198 tanks.

- Ukraine says Russia firing rockets into residential areas after failing to take Kharkiv and Chernihiv.

- A Russian missile attack on a government building in Kharkiv kills 10 or more and wounds 20, Ukraine says.

- Eight more die in a subsequent air strike on a Kharkiv residential building, Ukraine says.

- Russian army sets up checkpoints at southern city of Kherson, mayor says.

- Russia says fired long-range high-precision weapons from the sea, hitting two unspecified airfields and three air defence radars.

- Russian forces made little progress in past 24 hours and don't control Ukraine's airspace, British intelligence says.

- France sends hundreds more troops into Romania.

- NATO will "defend every inch" of its territory, alliance chief says.

The civilian/humanitarian situation:

- UN says 12 million people in Ukraine will need aid.

- One million people are displaced within Ukraine, and more than 677,000 have fled abroad, UN says.

- China begins evacuating nationals from Ukraine.

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