President Donald Trump has said a US plan to end the Russia-Ukraine war is not his "final offer" for Kyiv, after Ukrainian allies voiced concerns over proposals, BBC reported.

Earlier on Saturday, leaders from Europe, Canada and Japan said the plan had elements "essential for a just and lasting peace", but would "require additional work", citing concerns over border changes and caps on Ukraine's army. 

On Sunday, security officials from Britain, France, Germany, the US and Ukraine will meet in Geneva, Switzerland, according to BBC.