Ukraine is continuing to urge its Western allies to send tanks as the country fights against Russia's invasion.
Germany is under pressure to authorise the delivery of German-made Leopard 2 tanks to Ukraine, while the UK has already agreed to send 14 Challenger 2s.
But why does Ukraine want tanks so badly and how could they be operated?
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Tactically, what can tanks give to Ukraine?
Former Commander of 1st Royal Tank Regiment, Colonel (retired) Hamish de Bretton-Gordon, told Forces News: "Tanks are absolutely crucial for the next stage in this conflict."
Mr de Bretton-Gordon highlighted the tactical benefits tanks would play in progressing in a "vast country" such as Ukraine.
Due to the country's large area, Mr de Bretton-Gordon believes the war at the moment has become "very static", with "Russians dug into trenches".
"Ukrainians want tanks because that gives them manoeuvre, the ability to manoeuvre in large areas, very quickly and break through those static Russian lines, get behind the Russian forces, cut them off from their logistics support and is probably the surest way – but combined with infantry and artillery and air power – to defeat the Russians in Ukraine."
How does the Challenger 2 and other Western tanks compare to Russian tanks?
The British Challenger 2 main battle tanks heading to Ukraine means Russia would be fighting an undefeated platform – not once has the Challenger 2 been destroyed at the hands of an enemy.
Mr de Bretton-Gordon says: "Western tanks, particularly Challenger 2, vastly overmatch Russian tanks and the old Soviet tanks that the Ukrainians have at the moment."
The firepower in its main armament is a 120mm rifled gun, which is a "very accurate, very powerful gun, [that] can fire on the move accurately and probably, more importantly, can fire accurately at night, all the things Russian tanks can't do."
As well as the firepower, the former commander highlighted the Challenger 2s' Chobham (RPG-resistant) armour.
"As far as protection goes, Challenger 2 is very well protected, it would take a number of hits from a T-72 [Soviet-era tank operated by Russia] and the crew would survive", he said.
Mr de Bretton-Gordon added that in comparison, Russian tanks have "very little protection and we are seeing them destroyed in their thousands".
He also spoke about the Challenger 2s' "impressive" mobility.
"Although 40pmh doesn't sound very fast, for something approaching 70 tonnes, it is very impressive and you can cover a huge amount of ground," he said.
He recalled the last time he was in the tank, and how it covered "over 2,500 miles" with "absolutely no problems at all".
Will the mud season pose a problem?
Any tanks received by Ukraine will very likely be thrust into some challenging terrain, especially when temperatures rise and the ground becomes softer and muddy.
"The state of the ground is of course key," Mr de Bretton-Gordon said.
"At the moment, it is pretty frozen, so no problem for tanks there.
"Once it starts getting muddy, we have more of a challenge".
He did, however, highlight a significant advantage of the British Challenger 2s over the Russian tanks, saying: "It has much higher ground clearance, the distance between the hull and the ground.
"Therefore, it is less likely to get bogged in than Russian tanks."
Will it be easy for the Ukrainians to get used to the Challenger 2?
An issue that has been discussed is that Ukrainian troops originally would have trained on Soviet-era tanks – the kind of tanks that Russia is using.
However, Mr de Bretton-Gordon believes there will not be too many problems for the Ukrainians operating the "very easy to use" Challenger tank, highlighting its "almost PlayStation technology for firing the gun".
He added that "a lot of their crews are very experienced, there is very little we can teach them about tank warfare itself".
"Challenger 2 is very easy to use... when it comes to driving, it will be again very simple to do, won't be any challenge there and for the gunner."
However, he did highlight a possible challenge.
Mr de Bretton-Gordon said a lot of the Russian tanks only have three main crews, and have auto-loaders, whereas with the Challenger 2, you load the gun itself, but the retired colonel believes "this is not a complicated operation" for the Ukrainians.
He continued: "The next consideration would be the logistical support, but again, it's about diesel, getting enough diesel into these tanks, but Challenger 2 is relatively good when it comes to that.
"Other parts are very much plug and play, so if there is a problem with the engine you whip it out and you put a new one in and, again, I think that's well within the compass of Ukrainian mechanics to be able to pick that up pretty quickly."