The UK and its NATO allies have approved sending "new and heavier" weapons to Ukraine.
Britain’s Foreign Secretary, Liz Truss, said the alliance members have agreed at the headquarters in Brussels on Thursday to help Ukraine’s military upgrade their "Soviet-era equipment to NATO standard".
“We’ve agreed to step up support for Ukraine and we’ve also recognised that the conflict has entered a new and different phase with a more concentrated Russian offensive,” said Truss.
Previous reports had suggested that Britain’s Ministry of Defence was mulling sending more anti-tank and anti-aircraft missiles, as well as a reconnaissance or long-range patrol vehicle, such as the Jackal, or the Mastiff, from its Protected Patrol fleet, to Ukraine.
After chairing a meeting of allied foreign ministers in Brussels, NATO Secretary-General Jens Stoltenberg said that there had been a “clear message” that allies “should do more, and are ready to do more, to provide more equipment, and they realise and recognise the urgency.”
Stoltenberg stopped short of clarifying specifically which countries were stepping up supplies or what kind of equipment would be sent, adding:
“Rest assured, allies are providing a wide range of different weapons systems, both Soviet-era systems but also modern equipment.”
US Secretary of State Antony Blinken also confirmed that that the Joe Biden administration was looking at "new systems" to send to Ukraine, where Russia is conducting a special operation to "demilitarise and de-Nazify" its neighbour.
"We're not going to let anything stand in the way of getting Ukrainians what they need. We are looking across the board right now, not only at what we have provided ... [but] whether there are additional systems that would make a difference," said Antony Blinken.
On Wednesday, the US announced it would send Ukraine a further $100 million worth of Javelin anti-tank missiles, with the package also including 10 Switchblade 600 combat drones.
Last week, the US Defence Department announced it was providing an additional $300 million in military equipment to the Kiev authorities, including laser-guided rocket systems, unmanned aircraft, armoured vehicles, night vision devices, and ammunition.
The European Commission, on behalf of the EU, has also approved the disbursement of a €500 million (£416 million) loan to Ukraine to fund more arms.
Western officials have been scrambling to shore up Ukraine’s weapons systems driven by the belief that the next few weeks of fighting in eastern Ukraine will be pivotal as Russian forces reposition from the north towards the Donbass region in the east of the country.
Gen Mark Milley, the chairman of the Joint Chiefs of Staff, had echoed the opinion that a standoff in the “south-east, down around the Donbas, Donetsk region of eastern Ukraine” would be crucial.
"I think it is an open question right now how this ends," he surmised.
Emerging from talks with NATO counterparts, Ukrainian Foreign Minister Dmytro Kuleba said arms supplies must be boosted to Ukraine quickly.
“Either you help us now — and I’m speaking about days, not weeks — or your help will come too late,” said Kuleba, as he rattled off a wish-list of planes, land-based missiles, armoured vehicles and air defence systems.
Kuleba had also warned that a looming battle in the east would be similar to “Second World War” combat.
"The battle for Donbass will remind you of the Second World War, with large operations manoeuvres, the involvement of thousands of tanks, armoured vehicles, planes and artillery. Russia has its plan, we have ours – and the outcome of this battle will be decided on the battlefield,” said the Ukrainian Foreign Minister.
Moscow has repeatedly warned that the supply of lethal weapons to the Kiev authorities by Western states is a mistake which only increases casualties.
Russia launched a military operation on 24 February after the Donetsk and Lugansk People’s Republics (DPR and LPR) appealed for assistance amid ceaseless attacks from Kiev forces throughout an eight-year offensive targeting the predominantly Russian-speaking Donbass.
The Russian Defence Ministry underscored that Moscow had no plans to occupy the country, with the operation exclusively targeting Ukrainian military infrastructure.
Washington and its NATO allies have targeted Moscow with sweeping sanctions while continuing to supply weaponry to Kiev authorities.