As I said yesterday, the easiest intervention is taking in refugees, and all the chest thumping and preening is pretty ridiculous unless that's on the table. Big ocean between the US and Ukraine, of course, but not much distance between the
UK and Ukraine (many countries inbetween, but I can't follow all of their politics).
The UK has stopped accepting visa applications from Ukrainians stuck in the country, meaning there is no safe and legal route for them to seek asylum in Britain unless they have British relatives.