Britain is to send Challenger 2 tanks to Ukraine to bolster the war effort against invading Russian forces.
Additional artillery support is also to be sent by the UK to assist the Kyiv government in the face of Kremlin aggression.
The announcement comes after Sky News exclusively revealed the UK was considering supplying Ukraine with British tanks for the first time.
Explosions in Kyiv and Kharkiv as ‘massive attack’ expected – Ukraine war latest
The move makes the UK the first Western power to supply the Ukrainians with main battle tanks.
UK government insiders said the decision had to be made now in order to ensure Ukrainian soldiers could be trained in how to use the weapons before a likely spring offensive.
Ministers hope the announcement will encourage other allies to follow suit.
Following a call between Rishi Sunak and Ukrainian President Volodymyr Zelenskyy on Saturday, a Number 10 spokesperson said the two leaders had agreed on the “need to seize on this moment” after Ukrainian victories had “pushed Russian troops back”.
The spokesperson added: “The prime minister outlined the UK’s ambition to intensify our support to Ukraine, including through the provision of Challenger 2 tanks and additional artillery systems.
“The prime minister stressed that he and the whole UK government would be working intensively with international partners to deliver rapidly the kind of support which will allow Ukraine to press their advantage, win this war and secure a lasting peace.”
Mr Zelenskyy tweeted: “Always strong support of the UK is now impenetrable and ready for challenges. In a conversation with the prime minister, I thanked for the decisions that will not only strengthen us on the battlefield, but also send the right signal to other partners.”
Labour’s shadow defence secretary John Healey said: “Modern tanks are crucial to Ukraine’s efforts to win its battle against Russian aggression.
“The government has Labour’s fullest backing for military assistance to Ukraine.
“But ministers must move beyond ad hoc announcements and set out a plan for military, economic and diplomatic support through 2023 and beyond.
“As the first anniversary of Russia’s invasion approaches, this will help reassure Ukrainians that Britain will stand with them for as long as it takes and signal to Putin that things will get worse not better for Russia.”
Earlier this week, Western officials warned Ukraine would not be able to take back significant territory from Russia without an increase in fighting power, including tanks and other heavy armour.
The US has promised 50 Bradley tank-killing armoured vehicles in its biggest military assistance package to date for Ukraine.
Germany also announced it would supply around 40 Marder armoured personnel carriers and France promised wheeled AMX-10 RC tank destroyers.
Ukraine has long requested the mass-produced, German-made Leopard II tanks, used by several European allies, including Germany, Poland, Finland, the Netherlands and Spain.
Warsaw and Helsinki have already signalled a willingness to supply their Leopard tanks to Kyiv but this requires approval from Berlin because Germany holds the export licence.
