Russia has strongly criticised the visit to Washington by Ukraine’s Volodymyr Zelensky, accusing the US of fighting an indirect war against it.
President Joe Biden has pledged $1.85bn (£1.45bn) of military aid for Ukraine – including an advanced missile system to help guard against Russian attacks.
In a defiant address to US lawmakers, Mr Zelensky welcomed the assistance.
But Russia’s US ambassador said these “provocative actions” would lead to an escalation with severe consequences.
Anatoly Antonov told Russian state media that Moscow was “trying to appeal to common sense at all levels”, but talk of delivering the Patriot missile system to Kyiv was “deeply disturbing”.
Patriot missiles are capable, effective and expensive. The White House says they will help defend Ukrainians against “Russia’s barbaric attacks on Ukraine’s critical infrastructure”.
Moscow has complained that no calls for peace were heard during President Zelensky’s trip to Washington – with spokesman Dmitry Peskov describing this as proof that the US was fighting a proxy war with Russia.
Mr Peskov added that delivering Patriot missiles would not prevent Russia from “achieving its goals during the special military operation”.
Russian commentators have echoed this – repeatedly accusing the US of “pumping Ukraine full of weapons”.
Some media reports from Moscow ridiculed the Ukrainian leader – with state TV’s Channel One comparing him to a stripper begging for money. On Wednesday, he was likened to a toilet brush.
Marking his first foreign trip since the start of the invasion, Mr Zelensky told Congress his country was “alive and kicking” and would never surrender to Moscow.