A close ally of President Vladimir Putin warned Western governments on Thursday that a nuclear war would ensue if they gave the green light for Ukraine to use long-range Western weapons to strike targets deep inside Russia.

"We think it lays out a strategy and a plan that can work," she said. Miller told a news briefing Blinken had learned about the plan during a visit to Kyiv and shared the ambassador's assessment. He said Ukrainian President Volodymyr Zelenskiy had said he looked forward to presenting the plan in detail to President Joe Biden.