Military experts say Ukraine is about to enter a new phase of the war that will show whether it can recapture territory occupied by Russia since February before economic pressure on its economy becomes too great.
Neither Russia nor Ukraine is engaging in large-scale offensives at the moment, as they refit their ammunitions and weapons systems, said Matthew Schmidt, associate professor of national security and political science at New Haven University.
“We’re at a point of pause before a new phase begins,” Mr Schmidt said.
But exactly how much military support Ukraine will receive depends largely on delicate political considerations in countries such as the US and Germany.
Berlin is under intense pressure to allow countries such as Poland and Finland, which own its Leopard 2 battle tanks, to transfer them to Ukraine.
Senior western diplomats meeting on Friday at a US military base in Ramstein, Germany, at the invitation of US Secretary of Defence Lloyd Austin, are expected to announce new “heavier weapons” for Ukraine, Nato Secretary General Jens Stoltenberg said.
Ukraine has made its demands clear.
“I need 300 tanks, 600-700 IFVs [infantry fighting vehicles], 500 howitzers.” Gen Valery Zaluzhny, head of its armed forces, told The Economist in December.
While he is not expected to obtain as much as requested, experts say that the key question is whether the Ramstein meeting will set Ukraine on track to receive the kinds of capabilities that are necessary to move towards "combined-arms warfare".
Combined-arms warfare merges, for example, artillery support, tanks, aircraft and infantry vehicles, to complement each of these weapons’ respective strengths and mitigate their weaknesses.
"We hear reports that Russia is preparing a next round of mobilisation in April or so," said Rafael Loss, co-ordinator at the European Council on Foreign Relations.
“Ukraine needs to prepare for mobile defence as well as offensive manoeuvres, since they have the ambition to liberate occupied territory."
Although there has been much media speculation about what kinds of tanks Ukraine might receive — a move previously avoided out of fear of further escalation with Russia — other considerations are just as important.
“It’s not just about providing tanks," Mr Loss told The National.
"There need to be supply chains for ammunition and spare parts, as well as training for mechanics, if tanks are destroyed by Russian fire."
Ukrainian troops, who are being trained by the US to operate at a battalion level of several hundred troops using combined operations, are expected to engage in a major offensive in the next 30 to 90 days, Mr Schmidt said.
“If they can operate a combined arms manoeuvre at this level, with improved weapons, they have a shot at really changing the battlefield equation and even push the Russians out of some areas,” he said.
“Ukraine needs to see a commitment towards restocking artillery and long-range missiles because the military objective is to strike in the rear of Russian occupied territory and obstruct Russia’s possibility to sustain its forces inside Ukrainian borders.”
Battle tanks are used to break through enemy defensive lines, unlike infantry vehicles, which are meant to carry troops under fire.
Sweden on Thursday announced a new package of military aid to Ukraine that will include armoured infantry fighting vehicles.
Media reports have indicated that Germany is waiting for the US to send its own tanks, such as the M1 Abrams, before it will agree to send its Leopard 2s.
But defence experts said such a request makes little military sense.
“Abram tanks are too difficult to operate. They run on jet fuel,” Mr Schmidt said.
“It’s not the Americans saying: we don’t want to give the tank because it’s escalatory. They’re saying: it’s the wrong tool."
Germany’s Leopard 2 is the only European-made tank that has the capacity to be scaled up easily and enable large-scale training of armed forces along with easy access to ammunition and spare parts.
“Contributions from France, the UK and Italy can be meaningful but the problem with these systems is that they’re not produced any more,” Mr Loss said.
France said this month that it would send AMX-10 RC armoured fighting vehicles to Ukraine but has stopped short of transferring its Leclerc battle tanks.
Last week, Britain announced it would send 14 Challenger 2 battle tanks and 30 AS90 15mm self-propelled guns to Ukraine.
Some countries have clearly indicated that Germany is testing their patience. Poland’s prime minister on Thursday said he would send Leopard 2 tanks to Ukraine even without Germany’s re-export approval.
Mr Scholz’s hesitancy may in part be caused by his country’s trauma of the Second world War, Mr Loss said.
“This idea of German tanks going toe to toe with Russian tanks in eastern Europe is something that is historically really uncomfortable for some people,” he said.
Ukrainian President Volodymyr Zelenskyy has been urging western countries to put aside their fears over escalating the war against Russia and increase their support for Ukraine.
"The world must not hesitate today or ever," he said this week in a video call to the World Economic Forum in Davos, Switzerland.
Ukraine, which is expected to suffer a GDP contraction in 2022 of more than 30 per cent, may soon be running out of time.
“Ukraine is under a lot of pressure to train up and arm up in order to win the war fast,” Mr Schmidt said.
“For [Russian President Vladimir] Putin to win at this point, he just has to not lose so that he can drag the war out and put Ukraine under enormous financial pressure.”
EU members have so far provided €8 billion ($8.32 billion) in military support for Ukraine, the EU’s top diplomat Josep Borrell said in November.
The bloc will be disbursing €1.5 billion ($1.6 billion) in monthly aid to Ukraine this year.
The US is set to finalise a military aid package totalling about $2.5 billion worth of weaponry, CNN reported on Thursday.
In total, US aid to Ukraine in the past year has amounted to more than $100 billion.
There are concerns about how long average citizens in western countries will continue to support the war effort.
“It’s possible that public support can continue a little longer, but for two more years? I’d be sceptical of that,” Mr Schmidt said.