Putin warns Moscow’s response will be ‘instant’ if anyone intervenes

In a televised address to the Russian people, Putin said that the operation is aimed at the "demilitarisation and denazification" of Ukraine.

Missile strikes and explosions have been reported in several parts of Ukraine, including Kyiv and Kharkiv.

Ukraine's Foreign Minister accused Russia of starting a full-scale war and implored the UN to "do everything possible" to stop it.

US President Joe Biden has condemned the attack and vowed to hold Russia accountable.

Leaders from the UK, European Union, UN and NATO have also strongly condemned the Russian offensive.