In January 2022, Britain delivered the first batch of 2,000 new light anti-tank weapons (NLAWs) to Ukraine in response to the increased threat from Russia. This was despite the lack of concern amongst other western nations, including those on the European continent.
The delivery of these weapons before Russia had invaded was critical to assisting Ukraine's defence. There are estimates that Russia has so far lost (from the start of the conflict to the 9th of March) around 860 vehicles, including tanks and armoured vehicles. Many of these have been disabled or destroyed using anti-tank weapons, many of which have been supplied by Britain.
These weapons are lethal against Russian armoured vehicles and have proven extremely effective in stalling Putin's invasion force. Since then, we have delivered 3,615 of these NLAW missiles, and additional weapons such as Javelin anti-tank missiles, Starstreak anti-aircraft missiles, and additional defensive weapons and non-lethal aid such as body armour is beginning to enter the region.
Update 25/03/22: Britain is now sending an additional 6,000 missiles to Ukraine.