The Foreign Secretary is calling for allies to be "resolute" in their support of Ukraine, warning there are no "guarantees" of success in its upcoming military counteroffensive.
James Cleverly said Ukraine has "consistently outperformed" expectations in its response to Russia's invasion but international support is still required, despite the financial cost.
Speaking during a visit to the US, Mr Cleverly said: "Of course there has been an economic impact on the people of the United States and the United Kingdom – this is not a by-product of Russia’s invasion of Ukraine, this is part of the conflict.
"We should recognise that if we do not re-establish the principles of the UN charter - the foundation stone of peace in the post-Second World War era, that powerful nations cannot invade their neighbours with impunity - the world will be more dangerous, more expensive, more difficult.
"So this is not just about Ukraine, though the Ukrainians have been suffering enormously and it's right that we defend them, it is about us, and it is in our interest as well as in the Ukrainians' interest that we stay resolute in our support."
He added: "When it comes to the Ukrainians' forthcoming counteroffensive, I've made the point that this is not a film. There are no certainties when it comes to conflict – the Ukrainians have consistently outperformed expectations but there can be no guarantees in war…
"We need to continue to support them irrespective of whether this forthcoming offensive generates huge gains on the battlefield, because until this conflict is resolved and resolved properly, it is not over."
On Monday, air raid sirens sounded across Ukraine during the latest wave of Russian drone and missile strikes.
Moscow escalated attacks on the capital Kyiv and other cities ahead of the Russian Victory Day celebrations.
Ukraine says it destroyed all 35 Iranian-made drones launched by Russia overnight from Sunday into Monday.