Ukraine's ambassador to the UK received a standing ovation from British MPs in parliament.
Lawmakers in the House of Commons, including British leader Boris Johnson, rose to their feet and started applauding on Wednesday after Speaker Lindsay Hoyle revealed that Vadym Prystaiko was in the gallery to watch Prime Minister's Questions (PMQs).
The applause lasted just under a minute.
Hoyle addressed Prystaiko after, saying: "Your excellence, we generally do not allow applause in these chambers but on this occasion, the House quite rightly wants to demonstrate our respect and support for your country and its people in the most difficult of time."
Johnson then opened PMQs with a short statement in which he said that Russian President Vladimir Putin "has gravelly miscalculated in his abhorrent assault on a sovereign nation he has underestimated the extraordinary fortitude of the Ukrainian people and the unity and resolve of the free world in standing up to his barbarism".
"The UN General Assembly will vote later today and we call on every nation to join us in condemning Russia and demanding that Putin turns his tanks around. If instead Putin doubles down, then so shall we, further ratcheting up economic pressure and supporting Ukraine with finance, with weapons and with humanitarian assistance," he added.
Russia launched an attack against Ukraine on 24 February.
The UK, along with other Western allies including the EU and US, has riposted with economic and financial sanctions against Russia. These primarily targets banks, financial institutions and oligarchs close to the Kremlin with the aim of cutting Russia's ability to raise funds for its military.
Allies have also sent weapons to Ukraine and bolstered NATO positions along its eastern flank with additional troops and equipment.