The Prime Minister has urged western allies to continue to supply Ukraine with weapons and aid in its fight against Russian forces.
In a plea to the US and European powers, Rishi Sunak said President Volodymyr Zelensky’s armed forces would “finish the job” if given the tools they need.
Mr Sunak’s warning for the need to continue support for Kyiv comes as the international allied effort shows signs of wavering.
As he began his Conservative Party conference speech, Mr Sunak said: “I am proud to say we have also led the world in providing support for Ukraine.
“We were the first country to send western battle tanks to Kyiv, now more than 10 others have followed.
“We were the first country to send long-range weapons to Kyiv, now France and the United States have followed.
“We were the first country to agree to train Ukrainian pilots, now more than a dozen others have followed.
“I say this to our allies: If we give President Zelensky the tools, the Ukrainians will finish the job.
“Slava Ukraini.”
In the US, aid for Ukraine has been left in limbo despite efforts to avert a government shutdown, following opposition from a growing number of Republicans.
Slovakia has meanwhile witnessed a parliamentary election victory by a pro-Russian political party, which has suggested cutting military support for neighbouring Ukraine.
Poland and Ukraine’s formerly close relationship has also suffered in recent months due to disputes over grain and weapons.
Defence Secretary Grant Shapps visited Ukraine at the end of September to assure its leaders the UK was still committed to support the war effort.
But Mr Shapps’ suggestions that UK armed forces could offer “in country” training to Ukrainian soldiers were later downplayed.
The Prime Minister’s conference speech follows similar efforts to encourage camaraderie from the EU’s top diplomat, Josep Borrell.
“We are facing an existential threat. Ukrainians are fighting with all their courage and capacities, and if we want them to be successful, then you have to provide them with better arms, and quicker,” he said during a visit to Ukraine.