![Zelensky and Biden](https://ichef.bbci.co.uk/news/1536/cpsprodpb/4311/live/69ae7de0-5b4c-11ef-aeac-a3f48289fa1d.jpg.webp)
US officials are assessing how the incursion might reshape the political and military dynamics of the war, as well as the implications for Washington’s long-shifting stance on how Ukraine can use American-supplied arms.
The stunning raid, catching both Russian and apparently Western leaders by surprise, highlights one of the riskiest dilemmas for the Western-backed defence of Ukraine: President Biden has consistently tried to empower Kyiv to push back Russia’s invasion without risking an American escalation with Moscow. As President Putin has always tried to portray the conflict as a war between Russia and the West, Mr Biden has sought to put clear limits on US policy to deflate that narrative and prevent a conflagration.
But Ukraine’s Kursk assault - the largest incursion into Russia by a foreign military since World War Two, according to military analysts - has raised a series of urgent questions for the White House. Does it rapidly expand the boundaries of Washington’s set limits for how Ukraine can use American and Nato weapons systems? Does it risk crossing Russia’s red lines over Western involvement in the war? If not, has President Zelensky showed Washington he can call Mr Putin’s bluff?