Prime Minister Rishi Sunak led the UK in a "national moment of reflection" joined by wife Akshata Murty, as the first couple hung a blue and yellow wreath in the colours of the Ukrainian flag on the door of 10 Downing Street on Friday to mark the one-year anniversary of the Russia-Ukraine conflict.

The British Indian leader was accompanied by military personnel in Downing Street for the one-minute national silence at 11 am GMT to pay tribute to the "bravery and courage" of the Ukrainians who have been fighting on the frontlines since the conflict began on February 24 last year.

Alongside the Ukrainian Ambassador to the UK, Vadym Prystaiko, Sunak hosted members of the Ukrainian Armed Forces as well as representatives from the 10 nations supporting the government’s Interflex training programme in support of Ukraine.

"As we mark one year since a full scale war broke out on our continent, I urge everyone to reflect on the courage and bravery of our Ukrainian friends who, every hour since, have fought heroically for their country," said Sunak.

"I am proud that the UK has stood shoulder-to-shoulder with Ukraine through this horrific conflict. As I stand with brave Ukrainian soldiers outside Downing Street today, my thoughts will be with all those who have made the ultimate sacrifice to defend freedom and return peace to Europe," he said.

Operation Interflex is a British-led multinational training programme for the Ukrainian armed forces involving New Zealand, Australia, Canada, Lithuania, Norway, Denmark, The Netherlands, Sweden and Finland.

King Charles III also issued a statement from Buckingham Palace condemning the "unprovoked" attack and expressed hope the outpouring of solidarity may bring not only practical aid but also strength from the "knowledge that, together, we stand united".

"It has now been a year that the people of Ukraine have suffered unimaginably from an unprovoked full-scale attack on their nation. They have shown truly remarkable courage and resilience in the face of such human tragedy," said King Charles.

Earlier this month, Sunak had raised the possibility of adding longer-range weapons to the programme with President Volodymyr Zelenksyy during his visit to the UK.

On Friday, the British Prime Minister is set to raise the issue with G7 allies – including Canada, France, Germany, Italy, Japan and the US – in a virtual meeting as he calls on international partners to help Ukraine push back Russian forces.

"For Ukraine to win this war – and to accelerate that day – they must gain a decisive advantage on the battlefield. That is what it will take to shift [Russian President] Putin’s mindset. This must be our priority now. Instead of an incremental approach, we need to move faster on artillery, armour, and air defence," Sunak is due to say in his address.

"The coming weeks will be difficult for Ukraine, but they will also be difficult for Russia. They are over-reaching once again. So now is the time to support Ukraine’s plan to re-arm, regroup, and push forward," he will say, according to excerpts of his speech released by Downing Street.

Sunak’s central message to the world leaders will be that sophisticated western capability will help protect critical civilian infrastructure and preserve the frontline defences.

He is also expected to reiterate his offer of UK support to countries able to provide jets to Ukraine to help in the immediate conflict.

Downing Street said the capability step change underlines Sunak’s push to help Ukraine seize a window of opportunity to push back Russian forces and help Ukraine defend and regain territory for the long term.

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