It is in the interests of the UK (and all NATO countries) that Ukraine is supplied with everything it needs
a) to maintain their nations infrastructure to counter the criminal actions of Russia, and
b) to enable their armed forces to eject the Russian and mercenary forces from their territory, including Crimea.
Their is no point n any 'negotiated settlement' - Putins' previous actions have shown complete disrespect for any agreement.
If Russia succeeds in expanding it's borders by force now, it will not stop.