Ukraine is under heavy attack by Russian forces after Vladimir Putin finally gave the order for his invasion to begin.

Targets across the country have been hit by rocket strikes, including in the capital Kyiv, and there are reports some areas and border points have already fallen to Russian forces.

Hundreds are feared to have been killed already after a comprehensive attack on military targets and critical infrastructure. 

There has reportedly been heavy bombing in Odessa, the seat of Ukraine’s navy, which is feared to have been crippled already, although reports differ.

Troops are flooding into eastern cities like Kharkiv and Mariupol, witnesses have said.

Air raid sirens have sounded across the country – including in Lviv, where most diplomatic missions have moved to – and communication systems have been hit by cyberattacks.

Ukraine’s border guards said it was under attack ‘with the use of artillery, heavy equipment and firearms’ in the regions of Luhansk, Sumy, Kharkiv, Chernihiv and Zhytomyr.

It said Belarus’ armed forces – a Russian ally which lies to Ukraine’s north close to Kyiv – had joined in with the military assault, with at least one border point destroyed.

Videos posted on social media showed smoke rising above several Ukrainian cities and there are unconfirmed reports Russian paratroopers have moved to take control of Kyiv airport.

Russia’s ministry of defence claimed to have ‘disabled’ Ukraine’s air force and ‘incapacitated’ military infrastructure, according to state media.

Speaking from an undisclosed location, the president of Ukraine declared martial law and vowed the army would resist.

Ukraine’s defence ministry said it had shot down five Russian planes and a helicopter in its airspace.

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The attack began minutes after the Russian president concluded a televised address announcing a ‘special military operation’.

Mr Putin said the invasion would secure the ‘demilitarisation and denazification of Ukraine’ and threatened to ‘bring to court those who committed numerous bloody crimes against civilians’, referencing his unfounded claims Kyiv has persecuted Russian speakers.

Shortly before 4am GMT, Ukraine’s foreign minister said: ‘Putin has just launched a full-scale invasion of Ukraine. Peaceful Ukrainian cities are under strikes. 

‘This is a war of aggression. Ukraine will defend itself and will win. The world can and must stop Putin. The time to act is now.’

Boris Johnson will chair a Cobra meeting at 7.30am and fresh sanctions and other measures are expected to be announced by the West.

The Ukrainian government has appealed for military and humanitarian aid.

Russia has been steadily building a force of up to 200,000 on the border for several months, heavily outnumbering its neighbour’s army.

Ukraine’s military has been preparing for an assault with the assistance of Western allies but there is a gulf in capability between the two nations.

The conflict between the countries began in 2014 when a popular revolution saw the pro-Moscow government in Kyiv swept away.

In response, Russia annexed Crimea and Moscow-backed separatists forces in the eastern Donbas region declared their independence, triggering years of grinding conflict which has claimed thousands of lives.

Russian president Vladimir Putin penned a long essay last year setting out his ethno-nationalist belief that Ukraine is destined to be a part of Russia, a clear warning he did not intend to stop at the Crimean peninsula. 

US and UK intelligence has long warned Russia could use a range of military tactics to attack Ukraine.

As well as ground troops, naval forces in the Black Sea and aerial capability, Russia is also known to be adept at deploying cyber warfare.

Mr Putin has kept the world guessing about his true intentions in recent months and at times has appeared to suggest a willingness to engage with diplomatic talks, despite preparing for an incursion.

As well as troops and military hardware, satellites over Russia and Belarus have identified conflict infrastructure like field hospitals under construction close to Ukraine.

Tensions were ratcheted up once more on February 15 when Mr Putin accused Ukraine of ‘genocide’ against Russian speakers in the east of the country, a thinly veiled attempt to create a pseudo-legitimate pretext for invading.

Several senior figures have visited Vladimir Putin to try and convince him to pull back, including French president Emmanuel Macron and German chancellor Olaf Scholz.

UK prime minister Boris Johnson has held several rounds of high level talks with Western politicians and military figures in recent weeks.

Nato allies have ruled out a military response to any invasion but have promised to respond with an unprecedented package of sanctions, some of which were rolled out earlier this week after Moscow formally recognised the illegal republics in the Donbas region.

Recents months have also seen Nato military deployments on the continent’s Eastern flank bolstered with personnel and equipment, including from the UK.

The full-scale invasion comes after months of demands from Moscow about fundamentally reorganising defence arrangements in Europe.

The Russian president has demanded Ukraine be permanently blocked from joining the Nato military alliance, as well as calling for missiles to be moved away from Russia’s border.

Led by the US, Nato rejected Mr Putin’s key demands but signalled there was room for maneuver on some secondary issues.

Speaking after talks with Germany’s leader in the Kremlin, he said he was open to discussing disarmament and other changes to bolster relations between East and West.

But he made it clear there was still a huge chasm between his demands on what the West was willing to compromise on, pouring cold water on hopes of a deescalation.

This is a breaking news story, more to follow soon… Check back shortly for further updates.

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