Coco51 I think the Russians have air supremacy, which makes bombing the convoys difficult, the Russians will also have them protected by anti-aircraft guns
I understand, that the bridges across the River Dnieper, that cut the country in half have been charged ready to be blown up, but I have not seen confirmation of that.
We are supplying the Ukrainians with hand held heat seeking anti tank weapons, But it is a bit like Brtain deciding to invade the Isle of White, the sheer size and power of the invader, will in evitably overwhelm them in the end.