The United States has accused Russia of a “dangerous and inexplicable escalation” of its nearly four-year war in Ukraine, at a time when US President Donald Trump is trying to advance negotiations towards peace.The US issued its latest warning on Monday, during an emergency meeting of the United Nations Security Council.Recommended Stories list of 3 itemsend of list“Russia’s action risks expanding and intensifying the war,” Tammy Bruce, the US’s deputy ambassador to the UN, told the council.The US expressed particular alarm about Russia’s use of a nuclear-capable Oreshnik ballistic missile last week, which resulted in a “staggering number of casualties” in Ukraine.“At a moment of tremendous potential, due only to President Trump’s unparalleled commitment to peace around the world, both sides should be seeking ways to de-escalate,” Bruce said.Still, hours later on Tuesday morning, Russia launched a new round of strikes on Ukraine’s northeastern city of Kharkiv, killing at least four people and wounding at least six others.Missile strikes were also reported in the capital, Kyiv, but their impact could not be immediately assessed.Ukraine called for the Security Council meeting after Russia bombarded the country last Thursday with hundreds of drones and dozens of missiles, including the Oreshnik missile.That attack was only the second time Russia had launched the powerful Oreshnik missile in a combat scenario, and its use was widely interpreted as a clear warning to Kyiv’s NATO allies.At Monday’s meeting, Bruce reminded Russia that, nearly a year ago, it voted in favour of a UN Security Council resolution calling for an end to the conf …