The UK has already sent Ukraine large consignments of weapons, including more than 10,000 anti-tank missiles which have proven effective against Russian armour.
Ukrainian forces have also used US Stinger missiles to take down enemy aircraft.
But how does Ukraine defend against the Russian artillery threat? Cities such as Mariupol and Kharkiv have come under relentless fire from shells.
What can the UK contribute to Ukrainian defence? Britain has the AS-90 but it is complex and nearing the end of its life.
Justin Crump, a former British Army Tank Commander, told Forces News: "We thought that by now, Ukraine would be fighting an insurgency and actually they're still fighting a conventional conflict but with equipment for an insurgency.
"We haven't sent them enough of the right equipment. We're now moving towards equipping them for warfighting, probably at just the time they’re not going to have any fuel to be able to actually operate anything we send anyway."
"We've got a real bind as to what we actually send," he added.
Ukraine's air force flies the Russian-made SU-27, which is fast but lacks modern countermeasures.
Against it, Russia has the formidable S-400 air defence system, with the capability of hitting aircraft 150km away.
To try to level things up, the UK has sent STARStreak to Ukraine – a short-range missile that is used against low-flying aircraft and helicopters.
Footage has emerged reportedly showing it being used to down a Russian helicopter.
Defence Secretary Ben Wallace says the UK will help to protect the Ukrainian coastline from Russian warships and amphibious assault craft.
Last year, Britain signed a £1.7bn deal to supply Ukraine with minehunters and naval weaponry, but getting it to the country is difficult.
Watch: Ukrainian MP's 'we will rebuild' message after world's largest aircraft destroyed.
The Ukrainians could take a leaf out of the Iranian playbook and use small gunboats to harass the Russians at sea.
Dr Alessio Patalano, a senior lecturer in War Studies at King's College London, said: "The logic here if you could turn any single fast boat that you can find around the port into the maritime version of your Toyota pick-up for any insurgent fighting a war, that's already a very important consideration to make.
"Being able to deploy on a fast little, tiny craft, a bit of an RPG () or anything that would make it a lot harder for the Russians, to target these assets as well as to have the serenity, if you want, to plan an amphibious operation, that is already a win."
What else might Britain send?
Protected vehicles such as the Foxhound could go, or some other Afghan-era troop carriers, but spares and servicing are complicating factors.
There is an argument it would be more efficient to source ex-Soviet or Russian-made weaponry from around the world, like T-72 tanks – systems the Ukrainians have experience of.
The MOD remains tight-lipped about what it is sending, but in this age of social media, the first time UK contributions will be known will be when they are seen on the frontline.